Condensing Models

On-Demand Water Heater Service Handbook

MODELS: 160X3P 180X3P 199X3P (Indoor/Outdoor) (Indoor/Outdoor) (Indoor/Outdoor) Series 100 Series 100 Series 100

THIS SERVICE HANDBOOK IS FOR USE BY QUALIFIED SERVICE PROFESSIONALS ONLY. IF YOU NEED ASSISTANCE, CALL TECHNICAL SUPPORT. IN USA, CALL AT 8777372840. IN CANADA, CALL 8884798324.

DIR 2000585401 Rev. B March 2020 TABLE OF CONTENTS

SPECIFICATIONS ...... 4 INTRODUCTION ...... 5 General Installation Guidelines ...... 5 NORMAL OPERATION ...... 6 Activation ...... 6 Operation ...... 6 Shutdown ...... 6 Preliminary Checklist ...... 6 Gas/Water/Electric: ...... 6 TROUBLESHOOTING ...... 7 Remote Controller: ...... 7 High Altitude: ...... 7 Vent Length : ...... 7 X3TM Technology: ...... 7 New Installations: ...... 7 Test to determine if the problem is related to plumbing or the water heater: ...... 7 Next Step: ...... 8 General Issues ...... 8 Water is too hot or not hot enough...... 8 Temperature fluctuates when a fixture is opened...... 8 Unit does not operate when water goes through it...... 8 Abnormal sounds come from the unit...... 9 ERROR CODES ...... 11 Code 031: Incorrect DIP Switch Settings ...... 16 Code 051 or 101: Combustion Air and/or Exhaust Gas Blockage ...... 16 Code 111 or 121: Ignition Failure / Flame Loss ...... 16 Code 201: Combustion Air and Gas Line Failure ...... 17 Code 211: Air Pressure Sensor Failure ...... 17 Code 311, 321, 331, 341 or 351: Thermistor Failure ...... 18 Code 391: Flame Rod Failure ...... 19 Code 441: Flow Sensor Failure ...... 19 Code 511: Abnormal Main Gas Valve (MV) ...... 19 Code 521: Air Damper Failure ...... 19 Code 551: Abnormal Solenoid Gas Valve (SV1, SV2, and/or SV3) ...... 19 Code 611: Abnormal Fan Motor ...... 20 Code 631: Pump Fault ...... 20 Code 651: Flow Adjustment Valve Fault ...... 20 Code 661: Bypass valve fault ...... 21 Code 701: Computer Board Fault ...... 21 Code 711: High Limit Switch / Overheat Cutoff Fuse Circuit is Compromised ...... 21 Code 721: False Flame Detection ...... 22 Code 741: Remote Control Problem ...... 22 Code 751: Temperature Controller Problem ...... 22 Code 761: Communication Error in Easy-Link System ...... 22 Code 991: Combustion Air and/or Exhaust Gas Blockage (also Code 051 and 101) ...... 22

2 • On-Demand Water Heater Service Handbook for X3P Models DIP SWITCH SETTINGS ...... 25 WIRING DIAGRAM ...... 28 SERVICE PROCEDURES ...... 29 Filter/Drain Plugs Cleaning ...... 29 Checking for a Crossed Connection ...... 30 Checking for a Reversed Connection ...... 30 Checking the Inlet Gas Pressure and Pressure Drop ...... 30 Adjusting the Manifold Gas Pressure and Firing Rate ...... 31 Checking the Manifold Gas Pressure ...... 31 Adjusting Manifold Pressure ...... 31 Checking the Overheat Cutoff Fuse (OHCF) ...... 32 Checking the Flow Sensor ...... 32 Cleaning the Flame Sensor and Igniter Rod ...... 33 Easy-Link Connections with Previous Models ...... 34 DIP Switch Setting Easy-Link on the Computer Board ...... 34 Easy-Link Unit Number Display and Renumbering Procedure (for 199X3P Models Only) ...... 35 Diagnostic Mode ...... 36 Individual Unit ...... 36 Multiple Units in a Linked System ...... 37 MAINTENANCE ...... 40 REMOVING AND REPLACING THE EXHAUST PORT CAP ...... 42 REMOVING AND REPLACING THE FAN ASSEMBLY ...... 42 REMOVING AND REPLACING THE COPPER GAS PIPE ...... 45 REMOVING AND REPLACING THE VENTURI ASSEMBLY ...... 46 REMOVING, REPLACING, AND VERIFYING THE GAS ORIFICE ASSEMBLY ...... 47 REMOVING AND REPLACING THE MAIN GAS VALVE MV ASSEMBLY ...... 49 REMOVING AND REPLACING THE PRIMARY HEAT EXCHANGER ...... 50 REMOVING AND REPLACING SECONDARY HEAT EXCHANGER ...... 55 REMOVING AND REPLACING THE IGNITER FLAME ROD ASSEMBLY ...... 59 REMOVING AND REPLACING THE THERMISTORS ...... 60 REMOVING AND REPLACING THE WATER PIPING SYSTEM COMPONENTS ...... 61 REMOVING AND REPLACING THE RECIRCULATION PUMP...... 64 REMOVING AND REPLACING THE DRAIN PORT AND DRAIN TUBE ...... 65 REMOVING AND REPLACING THE THERMISTOR INLET PLUG ...... 67 COMPONENT DIAGRAMS ...... 68 COMPONENT DIAGRAMS/ITEM NUMBERS ...... 73

On-Demand Water Heater Service Handbook for X3P Models • 3 BASICS SPECIFICATIONS •On-Demand Water Heater Handbook for Service X3PModels 4 a.wtrfo aeGM(/i)65(5 . 3)10.0(38) 3/4”NPT 1/2”NPT 15-150(0.11) 8.0(30) 6.5(25) lnlet Pressure psi(MPa) GPM(L/min) Propane lnlet Pressure Natural gas Max. water flowrate Water Pressure* Water Connections Gas Connection (Operating Range) Propane Input The manufacturer reserves theright to discon • Checkthera • NOTE: **** Refer to page 36intheInstallation Manualfor additionalinformation onpipelengths. *** TheManifold Pressure isthefactory setting andshouldnotneedadjustment. NOTE: Manifold Pressure readings are taken ** 40psi(0.27MPa) orabove isrecommended for maximum flow. * Dedicated Return line) (Hot Water supplylineand (Operating Range) Natural GasInput Table 1: Maximum PipeLength**** egtls k)68.8(31.0) (kg) lbs. Ignition Dimension Weight Electric Manifold Water Heater Vent Category cause excessive condensate production inthevent. Category IV with thefront cover removed. incurring obliga Consumption Pressure** Water Heater Vent Category*** tnb / 1.2/0.04 129.5/1.10 W/A W/A Freeze-Protection Standby inchW.C. (Pa) NG PinchW.C. (Pa) LP Operation upyVCH 120/60 VAC/Hz Supply -awater heater that operates withapositive vent static pressure andwithavent gas temperature that may ng plate to ensure thisproduct matches your speci on. / upWA13814 0./.013814 0./.013814 107.0/1.30 113.8/1.41 107.0/1.30 113.8/1.41 107.0/1.30 113.8/1.41 W/A W/O Pump Model /upWA126.7/1.55 W/A W/Pump BTU/h BTU/h inch W.C. (kPa) inch W.C. (kPa) nhsH27.4xW17.7D11.2 inches mH696xW450D285 mm -Doesnotapplyto Outdoor orDirect Vent Installations. Diameter Pipe MAX: MAX: MAX: MAX: MIN: MIN: MIN: MIN: /”200ft(61m) 500ft(152.4m) 1/2” 3/4” nue, orchange at any Category 160X3P Indoor IV -0.5 (-124.5) -0.06 (-14.9) -0.4 (-99.6) 0.05 (12.5) 160,000 160,000 9,000 9,000 Outdoor 160X3P fi ca N/A ons. me, speci Category 180X3P Indoor fi Max. 13.0(3.24) Max. 10.5(2.62) ca Electric Ignition IV Min. 8.0(1.99) Min. 3.5(0.87) -1.26 (-313.8) -1.26 (-313.8) -0.06 (-14.9) -1.12 (-279) 0.05 (12.5) ons or designswithoutno 180,000 180,000 9,000 9,000 Outdoor 180X3P N/A Category 199X3P Indoor IV -1.26 (-313.8) -0.06 (-14.9) -1.12 (-279) 0.05 (12.5) 199,000 199,000 ce and without ce and without 9,000 9,000 Outdoor 199X3P N/A BASICS on onsult the ving, Replacing, This water heater’s gas heater’s This water If this unit does not match your If this unit does not match Guidelines NOTE: NOTE: type is field convertible, confirm the confirm type is field convertible, type the gas matches orifice installed supplied. See Remo the Gas Orifice and Verifying 47. Assembly on page NOTE: do not install. requirements, absence of local codes, follow the follow codes, absence of local Fuel of the National edition current 54 in Gas Code: ANSI Z223.1/NFPA Gas andB149.1 (Natural or the USA Code) in Canada. Installation Propane codes with all local accordance codes, in the absence of local or, Codes: Electrical with the National or CSA 70 in the USA ANSI/NFPA Canada Electrical C22.1, standard 1 in Canada. Code, Part heater. water your install for heater side of the water the right WATER GAS PRESSURE, the correct and GAS RATING ELECTRIC PRESSURE, TYPE. General Installa General If any problem occurs, turn off all hot turn off occurs, problem If any Then the gas. and turn off taps water or the gas technician a trained call company. If you have any problems or questions or questions problems any have If you c this equipment, regarding 1. or in the codes, all local Follow 2. in the unit ground Properly 3. to intend you plan where Carefully 4. on located plate Check the rating technical service department or the local service department technical service agent. . If ankless page 11 page

CAUTION you have not received an error an error not received have you Issues” on “General to refer code, 8. page If the water heater is in fault and is in fault heater If the water refer code, an error is displaying Codes” on “Error to Before troubleshooting a new troubleshooting Before use the installation installation, manual. go first troubleshooting, Before Checklist” “Preliminary the through the most 6. It will identify on page and problems and frequent common knowledge with general you provide down the information help narrow to need. you First, refer to the Installation the Installation to refer First, Manual as the primary source it along to Refer of information. the side this manual throughout process. troubleshooting are if you troubleshooting, Before unit with how a tankless unfamiliar “Normal Operation” read operates, 6. on page On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 5

● ● ● ● ● water heaters. It will be effective in It will be effective heaters. water needs as troubleshooting helping your in followed are long as the instructions use is how to Here order. the intended this manual: Wear eye protection during water during water protection eye Wear or disassembly. assembly heater personal do so could lead to to Failure injury. the necessaryThis handbook provides the troubleshooting for information 180X3P and 199X3P t 160X3P,

indicates a hazardous a hazardous indicates indicates a hazardous a hazardous indicates indicates a hazardous a hazardous indicates indicates practices not practices indicates symbol. It is used to alert It is used to symbol. physical potential to you This is the safety alert This is the safety

CAUTION NOTICE WARNING WARNING DANGER WARNING Failure to comply with these warnings comply to Failure fire, explosion, in death, result could poisoning. monoxide or carbon The installer/service agent (licensed agent The installer/service for is responsible professional) or servicing your installing correctly with compliance and for heater water and local state/provincial, all national, codes. Installation and service must be and service must Installation by a qualified installer performed (such as a licensed plumber or gas fitter).

situation that, if not avoided, could if not avoided, that, situation injury. in minor or moderate result injury. physical to related situation that, if not avoided, could if not avoided, that, situation injury. or serious in death result situation that, if not avoided, will if not avoided, that, situation injury. or serious in death result ● ● ● injury hazards. Obey all safety all safety Obey injury hazards. to this symbol follow that messages damage, possible property avoid Do not remove serious injury or death. labels, or instructions, permanent any the outside either from plate the rating of the or the inside heater of the water access panels.

Read and follow all safety messages messages all safety and follow Read handbook and in this and instructions labeling. on the product INTRODUCTION BASICS NRA OPERATION NORMAL •On-Demand Water Heater Handbook for Service X3PModels 6 Ifthewater flowexceeds thewater 7. Thefan willmodulate andthe 6. Onceaflameisdetected, the 5. Thegas valve willopen.You will 4. TheIgniter generates asparkto 3. Thefan activates to purge thesystem. 2. Ahotwater fixture isopened.The 1. it shouldoperate asfollows: gas, water, andelectrical connections, is properly installed withappropriate help to troubleshoot it.Assumingit water heater normallyoperates may Becoming familiar withhowatankless valve willrestrict theflowto ensure desired temperature, theflowcontrol heater’s capabilities to heat to the demand. energy inputrequired to meet the adjust basedontheamount of gas solenoidvalve assemblywill controller.) temperature controller orremote (This green LEDislocated onthe green “InUse”LEDwillactivate. hear adeep“clunk clunk”noise. ignite thegas. heater willremain instandby. for NGandLP. the Otherwise, requirement whichis9,000Btu/h enough to meet theminimuminput temperature risemust begreat heater willbeginoperation. The than the0.4GPMbefore the through theheater that isgreater flow sensormust detect aflowrate Ac Opera va on on . Theheater willclosethemain 9. Theheater willstop heating when 8. together. multiple water heaters are linked bypass valve isalsousedwhen due to corrosion anderosion. The reduce damage to theheat exchangers the desired outlet temperature and like amixingvalve. Ithelpsto maintain NOTICE: Thebypasscomponent acts Figure 1: not beaccurate to theunit’s physical description. extinguishing theflame. gas valve andsolenoidgas valves, the deactivation point of0.26GPM. the water flowrate drops below the water heater. whenever flowisrestricted through loss ofpressure at hotwater fixtures temperature. Thiswillresult ina delivery ofwater at thedesired Water control valve

ZĞĐŝƌĐƵůĂƟŽŶWƵŵƉ The purposeofthisdiagram isto illustrate tankless water heater designconcepts, andmay Shutdown Gas solenoidvalve /Flow sensor Bypass valve Thermistor Thermistor Thermistor Thermistor Return line Gas valve Flame rod Hot water Heater Hi-limit Fan motor Fan KƌŝĮĐĞ naeExhaust Intake Venturi Cold water Issues,” ifnecessary. topics. You may alsorefer to “General To get started, review thefollowing 12. 11. 10. • Gas/Water/Electric: mode. The heater willenter standby to 1-½minutes. The length ofpost-purge can last up purge any remaining exhaust gases. The fan willincrease inspeedto LED willturnoff. detects aflame,thegreen “InUse” When theflamesensornolonger and thegas typeshownonthe gas, thegas typeDIPswitch, is beingused.Checkthesupply Verify that thecorrect gas type Condensate drainport Gas Preliminary Air adjustment valve Exhaust duct Secondary heat exchanger Metal knitburner Thermo switch ;ŽŵďƵƐƟŽŶĐŚĂŵďĞƌĂƐƐĞŵďůLJͿ Stepping motor Primary heat exchanger Igniter KǀĞƌŚĞĂƚƵƚŽī&ƵƐĞ;K Igniter rod X3 Checklist Pressure sensor PCB TM Exhaust thermistor Filter .H. ͘&Ϳ NORMAL OPERATION / TROUBLESHOOTING

rating plate. All four must be page 25. Also, see the installation missing check valve, or a the same in terms of gas type, manual for venting requirements. cartridge in a single-handle and your water heater model Incorrect vent length settings may faucet that needs to be must be converted for use with result in the reduced output from the replaced. that type of gas (natural gas or water heater. ◦ A dirty inlet filter. A dirty LP). NOTE: This water heater’s gas inlet filter can either prevent type is field convertible, confirm the X3TM Technology: water from flowing through orifice installed matches the gas type the water heater entirely, or supplied. See Removing, Replacing, This water heater is equipped with X3™ Scale Reduction Technology to create turbulence that can TROUBLESHOOTING and Verifying the Gas Orifice prevent the flow sensor from Assembly on page 47. inhibit scale formation within the heat exchanger tubing of this unit. Part measuring the water flow. • The gas supply valve should be of the X3™ Technology’s anti-scale ◦ Misconfiguration of the Easy- fully open and the gas line purged protection comes from the special X3™ Link system (if applicable). of air and debris. cartridge. The X3™ cartridge must be ◦ Gas line that has not been installed into the manifold located on purged of air correctly. • The water supply valve should be the underside of the heater cabinet fully open and purged of air and prior to operation of the unit). The debris. Test to determine if the X3™ system is designed to be hassle- problem is related to plumbing free; eliminating the need to drain • The unit must be connected to a the heater for installation, removal, or the water heater: 120 VAC 60 Hz power supply. or replacement of the cartridge. X3™ 1. Test whether the problem is • There is a power switch inside Scale Reduction Technology reduces within the unit or external to the the heater, located to the left of the formation of scale in the heat unit (i.e., in the plumbing system) the control board, that must be exchanger, extending the operating by attempting to run hot water turned on before the heater can life of the unit in typical potable water locally through the isolation valve operate. installations. Specific water conditions (if installed). Ensure that the hot may impact the efficacy of X3™, water shutoff is closed on the hot Remote Controller: such as excessive iron or manganese and return lines while running levels. Refer to the guidelines below water through the pressure relief If you are using a remote controller, and consult a water quality expert valve or hot isolation valve drain the remote’s ON/OFF button must be to determine if your water is within port. See Figure 2 on page 8. turned on. Press the ON/OFF button acceptable X3™ and EPA guidelines. on the remote until the amber Stand- 2. Does the heater ignite and continue By LED is lit. to run properly? If it runs properly, New Installa ons: the plumbing system is at fault. If High Al tude: If a newly installed water heater won’t the heater shuts down with an operate at all or operates erratically, error code or no operation occurs, If the heater is installed at an altitude of check for the following: the problem is with the water over 2,000 feet, it may cause a lack of air heater. NOTICE: If no error code is and incomplete combustion. See “DIP ◦ Reversed hot and cold displayed, you can use Diagnostic Switch Settings” on page 25. plumbing connections. The water heater must sense Mode to review stored error codes. Vent Length water flow to initialize See “ERROR CODES” on page 11 operations. Water flowing The length of your vent run may through the heater backwards require changes to your DIP switch will not activate the flow settings. See “DIP Switch Settings” on sensor. ◦ Cross-connections may be related to a recirculation pump, a defective mixing valve, a bad check valve, a

On-Demand Water Heater Service Handbook for X3P Models • 7 TROUBLESHOOTING •On-Demand Water Heater Handbook for Service X3PModels 8 • enough. Water istoo hotornot Proceed to the • • Table 2starting onpage 11. page 11.Seealsotheerror code chartin LED onthecomputer board. SeeFigure 3, controller) andbyflashcodes onthegreen the temperature controller (orremote code. Theerror code willbedisplayed on Finally, checkto seeiftheunit hasanerror Next Step: Figure 2: help: error codes, seeif thefollowing items common problems that donotinvolve if anerror code isidentified. For other temperature setting may beset of thewater heater? The What istheset temperature to “General Issues.” If there isnoerror code, proceed to “ERROR CODES” onpage 11. If itisdisplaying anerror code, proceed “C” Closed “A” Open Gnrl Issues General Outlet Hose

Water flowtest. (Hot) Bucket “Error Codes” CD A On-Demand HC Heater Water return line. valve on NOTE: Close B “D” Open “B” Closed section • • • fi Temperature • • • • • xture isopened. each point-of-use. (temperature limitingvalves) at install Thermostatic MixingValves To reduce theriskofscalding, inlet water temperatures. NOTE: Solar installation can have higher temperature orremote controller. can beadjusted usingthe too highorlow. Thetemperature in fluctuating outlet temperature. altitude andvent length can result setting. Incorrect settings for Check DIPswitches for correct unit system. Easy-Link misconfiguration inmulti regulator sizing. Incorrect gas supplyline and/or water linesandhotwater lines. Cross plumbingbetween cold Clean thethermistor andrecheck. could cause itto read incorrectly. present onthethermistor. This malfunctioning ordebrismay be The outputthermistor could be instructions. the mixingvalve manufacturer’s be adjusted orcleaned.Refer to The mixingvalve may needto temperature setting at thevalve. proper installation andcheck If amixingvalve isinstalled, verify Refer to theinstallation manual. Link system isset upcorrectly. unit system, verify that theEasy- If theunitisinstalled inamulti- unit (i.e.,plumbingsystem). within theunitorexternal to the Test whether theproblem is fl uctuates whena • water goesthroughit. Unit doesnotoperate when • • • blown. fuse inthebox assemblyis is set to theonposition,orif right ofthetemperature controller to seeiftheON/OFFbutton to the it willturnon.Ifnot,thencheck button onthecontroller to seeif If isnotlit,press theON/OFF temperature/remote controller. theamberLEDon observing in standby. Thiscan beverified by Check to seeifthewater heater is pump. or consider aconstant pressure the pressure difference and/ to seeifanadjustment can reduce tank. Checkthepressure settings well pumpischarging thebladder operation willfluctuate whenthe On well systems, theheater’s outlet temperature fluctuations. supply water system willresult in Fluctuations inpressure ofthe onpage 29. Cleaning” should beclean.See”Filter/Drain Plugs The filter onthecold water inlet 29. onpage Drain PlugsCleaning” lights upbeside“flow.” See”Filter/ front oftheunituntil thearrow pressing theinfo button onthe You can verify theflowrate by opening upmore hotfixtures). drawn through theunit(e.g., increase demandofwater being See iftheunitinitiates whenyou Is theflowrate over 0.4GPM?

TROUBLESHOOTING ving, This water NOTE: NOTE: If you cannot identify the source the source identify cannot If you the technical of this issue, contact service department. Check the rating plate to ensure ensure to plate Check the rating type is applied gas the correct that the unit. to type is field convertible, gas heater’s matches the orifice installed confirm supplied. See Remo type the gas the Gas and Verifying Replacing, 47. Orifice Assembly on page for settings Check the DIP switch type. and gas altitude length, vent Check the fan for debris. for fan Check the in the exhaust blockages Check for air line. and intake vent proper for Check terminations flue gases ensure to clearances the into not being drawn are air intake. combustion supply gas proper Check for pressure and allowable pressure drop. On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 9 • • • • • • • Abnormal sounds come from sounds come Abnormal the unit. If the fan does not initiate at all and at does not initiate If the fan to is power there that it is verified not the unit, the flow sensor may Check the properly. be working impeller proper flow sensor for functionality See “Checking the 32. page Flow Sensor,” New installations only: Are the hot only: Are New installations the to connections water and cold (hooked reversed heater water flowing in Water up backwards)? will not be the heater through reverse by the flow sensor and thedetected See will not operate. heater water Connection” a Reversed “Checking for on checking details 30 for on page connection. a reversed for Is the inlet water temperature temperature water Is the inlet point the set close to is too by opening Verify temperature. and check to multiple faucets operates. heater see if the water operates heater If the water a seasonal/ indicate this may causing condition geographic is too that water inlet warmer set heater’s the water close to The minimum input is point. 9,000 btu/h which means the if the will not activate heater input is below this. For energy and review systems, recirculation differential the temperature adjust as necessary. setting Check that the filters on the cold on the cold the filters Check that clean. lines are and return Make sure that a check valve a check valve that sure Make line. on the return is installed or missing A malfunctioning a cross will cause check valve to water allowing cold connection, the system. into back-feed • • • • • TROUBLESHOOTING 10 • On-Demand Water Heater Handbookfor Service X3PModels THIS PAGE ISINTENTIONALLY BLANK TROUBLESHOOTING

ontroller ontroller See Error Code 991 See Error Code 991 Computer board Computer Check the DIP switch settings on the PCB (Part #701). on the PCB (Part settings Check the DIP switch heater. heater. them together. unplugged and connect which you wires will connect they One end is male and the other is female; together. as necessary. troubleshoot 3. of the the bottom from both linking wires Disconnect 4. of both linking the ends end unit, take If the unit is not an 5. back on, then heaters the water to power Turn setting ERROR ERROR CODES On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 11 SYMPTOM OR ISSUE OR SYMPTOM PROCEDURE TROUBLESHOOTING Exhaust Gas Blockage Exhaust Exhaust Gas Blockage Exhaust Combustion Air and/or Air and/or Combustion Combustion Air and/or Air and/or Combustion Error code indicator on code indicator Error controller the remote Flashes Flashes If there is a problem with the unit, a numerical error code will display on the temperature c on the temperature will display code error with the unit, a numerical is a problem If there GREEN LED ON LED GREEN COMPUTER BOARD COMPUTER The ON/OFF button on the water heater and heater on the water The ON/OFF button 031 One Flash DIP switch Incorrect 051 Three 101 Five Error code indicator on code indicator Error controller the built-in Error Code Indicators. Error

Link system. Link system. heater. the water to power disconnect does NOT remote heater. the water to power disconnect physically must You ERROR CODE ERROR Figure 3: Figure All units have self-diagnostics. self-diagnostics. All units have of indoor models or on the TM-RE43 Remote Controller (if installed). Installation related problems can also produce an error an error produce also can problems related Installation (if installed). Controller on the TM-RE43 Remote of indoor models or pattern. will flash a code board LED on the computer not working, the green are controllers If the remote/temperature code(s). (The green LED is located beside the DIP switches as shown in Figure 3). as shown in Figure beside the DIP switches LED is located (The green If you are working with a water heater that is part of an Easy- that heater with a water working are If you the unit as troubleshoot you that recommend we Link system, these Follow system. an individual unit and not as part of the a child unit: troubleshooting prior to steps Table 2: 2: Table and Flash Codes Error 2. heater. the water to valves Close isolation 1. in the Easy- heaters all the water to power Disconnect TROUBLESHOOTING 12 • On-Demand Water Heater Handbookfor Service X3PModels ERROR CODE 1 r11TreFahsIgnitionfailure /Lossof Three Flashes 111 or121 5 Two Flashes 351 3 w lse Outlet thermistor failure Two Flashes Inlet thermistor failure Two Flashes Two Flashes 341 331 321 1 ToFahsHeat Exchanger Two Flashes 311 1 he lse Airpressure Three Flashes 211 0 n ls Combustion air OneFlash 201 COMPUTER BOARD GREEN LED ON YPO RISETROUBLESHOOTING PROCEDURE SYMPTOM OR ISSUE Exhaust thermistor and gas linefailure Thermistor Failure Return thermistor sensor failure failure failure flame troubleshooting. Verify thermistor resistances, • seepage18for thermistor thermistor (Part #407,408,411,715,718,731). Check for connection/breakage ofwiresand/or debrison • 715), burnmarks onthecomputer board(Part #701). Check for connection/breakage ofwires(Part #123, on thecomputer board(Part #701). • Checkfor connection/breakage ofwires,burnmarks properly. • Checkifthefan motor (Part #103)isfunctioning properly. • Checkifthepressuresensor(Part #123)isfunctioning continues to tripcontact technician. aqualifiedservice and feel itclickwhenresetting. Ifthehighlimitswitch the button willreset theswitch. Iftripped, youwillhear properly. Theswitch hasabutton initscenter, pressing • CheckiftheHi-limitswitch (Part #412)isfunctioning #413) andconnections to thegasvalvePart #102). hi-limit switch (Part #412),overheat-cut-off fuse(Part into combustion. Ifnothingisheard,thencheckthe valve assembly(Part #130)whenwater heater goes • Listen for the“clunk” soundcoming fromgassolenoid maybe theissue. combustion, ifnotheardthentheigniter (Part #710) burner (Part #101)when thewater heater preparesfor • A“buzzing”ignitionsoundshouldbecoming fromthe flame rod(Part #108). on thecomputer board(Part #701),and/or sootonthe • Checkfor connection/breakage ofwires,burn marks TROUBLESHOOTING and/or soot on the Flame rod (Part #108). (Part Flame rod soot on the and/or • Check for connection/breakage of wires (Part #402, wires (Part of connection/breakage • Check for 715). flow sensor impeller (Part debris on the • Check for #402). lines, verify the water in is installed • If a check valve(s) operating properly. are that they may have more pressure drop• The circulation lines push through. A Qualified to than the pump is designed a pressure drop perform will need to Service Technician calculation. check if the DIP switch • If a cross over valve is installed, p. 25.) to (Refer is correct. setting of blue and brown connection/breakage Check for burn marks gas valve assembly and/or wires going to #701). board (Part on the computer is #122) • Check if the air damper assembly (Part functioning properly. #122, of wires (Part connection/breakage • Check for #701). board (Part on the computer 715), burn marks Check for connection/breakage of the blue and green, connection/breakage Check for gas valve assembly blue, and red wires going to light #701). board (Part on the computer burn marks and/or buildup of wires, dust connection/breakage • Check for the on burn marks #103) and/or (Part motor in the fan #701). (Part board computer wire connectors of the corrosion/damage • Check for #103). (Part blockages, any for air intake • Inspect your exhaust are found. clear if any of wires in the pump connection/breakage • Check for 738). #726, (Part flow through the pump. water the reverse • Check for the water line to a check valve on the return Install proper operation. Verify heater. e #709) (Part of wires connection/breakage for Check or SV3) valve (MV) valve Flame Rod Failur Flame Rod Flow Sensor Failure Abnormal main gas Abnormal main gas On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 13 valve (SV1, SV2, and/ SV2, (SV1, valve SYMPTOM OR ISSUE OR SYMPTOM PROCEDURE TROUBLESHOOTING Abnormal gas solenoid Abnormal gas Six Flashes Six Flashes Six Flashes Air damper failure Two Flashes Two Two Flashes Two GREEN LED ON LED GREEN COMPUTER BOARD COMPUTER 441 391 511 521 551 611 Flashes Four 631 fault motor Fan Flashes Four Pump fault ERROR CODE ERROR TROUBLESHOOTING 14 • On-Demand Water Heater Handbookfor Service X3PModels ERROR CODE 5 N/A 751 4 N/A False flamedetection 741 SixFlashes 721 1 OneFlash 711 6 Four Flashes 701 661 5 Four Flashes 651 6 N/A 761 COMPUTER BOARD GREEN LED ON n ls Computer board fault One Flash Gas solenoidvalve drive Communication error in between water heater between water heater and remote controller and built-in controller YPO RISETROUBLESHOOTING PROCEDURE SYMPTOM OR ISSUE Communication error Communication error Bypass valve fault Flow adjustment circuit failure valve fault Easy-Link reset. System. Turn theParent water heater OFFthenON to heater without first powerto turningoff theEasy Link if youdisconnect anEasy LinkwirefromaChildwater • Thecode will onlyappearontheParent water heater Child unitswithoutpower. • ChecktheChildunitsfor power. Troubleshoot any the childunitsarecorrect. Refer to pp.34and37. • Checkiftheconnections between theparent unitand to reset. to thewater heater. Turn thewater heater OFFthenON from thewater heater without first power turningoff • Thecode willappearifyoudisconnect theremote and built-in controller. • Inspecttheconnections between thewater heater to reset. to thewater heater. Turn thewater heater OFFthenON from thewater heater without first power turningoff • Thecode willappearifyoudisconnect theremote and remote controller. • Inspecttheconnections between thewater heater • Verify thecorrect model/typeofremote isinstalled. buildup. Check theflamerod(Part #108)for corrosion/soot Refer to the111and121errorcodes. (Part #701,714). Check for connection/breakage ofwiresorburn marks blocking • Inspectthecontrol valvefor debristhatmaybe breakage ofwires. • Inspectthebypass valve(Part #403),for connection/ blocking it. • Inspectthecontrol valvefor debristhatmaybe connection/breakage ofwires • Inspecttheflowadjustment valve(Part #402),for TROUBLESHOOTING matches gas type orifice plate installed. DO NOT DO NOT installed. plate gas type orifice matches do not match; if they heater water the operate immediately. correct and verify switches the DIP is installed, heater water the proper elevation. to are set venting installed length of the vent equivalent 5 on page 27. See Table to Refer system. are found. clear if any the between is proper clearance there check whether to Refer terminal. and the exhaust air terminal intake and Use & Instructions 28 of the Installation pp. 26 to Care Guide. is not #007) and verify air intake tray (Part protection blocked. #701) board (Part on the computer marks • Verify the gas type supplied to the water heater the water to the gas type supplied • Verify heater. the water around • Inspect the environment of the area where the • Check the altitude/elevation the match length DIP switches the vent • Verify blockages, any for air intake • Inspect your exhaust system, as a direct-vent installed is heater • If the water of the rain and dirt on the air screen dust • Check for burn of wires and/or connection/breakage • Check for On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 15 Exhaust Gas Blockage Gas Exhaust SYMPTOM OR ISSUE OR SYMPTOM PROCEDURE TROUBLESHOOTING GREEN LED ON LED GREEN COMPUTER BOARD COMPUTER 991 Flashes Five Air and/or Combustion ERROR CODE ERROR TROUBLESHOOTING Blockage Air and/or Exhaust Gas 16 • On-Demand Water Heater Handbookfor Service X3PModels Verify that thegas supplypressure is 1. external cause, suchasnogas supply. component intheheater ordueto an These codes can appeardueto a failed ignition attempts (code 121). able to establish aflameafter three during aheating cycle andwas not (code 111)oritlost theflame signal after three failed ignitionattempts Either thewater heater willnotfire Failure /FlameLoss Code 111or121:Igni Refer to “Error Code:991,“ page 22. Code 051or101:Combus After setting theDIPswitches, turn 3. Remove front cover andlocate 2. Turn off thepower supply. 1. the heater power was on. or DIPswitches were changed when incorrect DIPswitch setting isdetected The system displays thiscode whenan Se Code 031:Incorrect DIPSwitch within specifications when the heater is within specifications whentheheater is power to thewater heater backon. computer board. the DIPswitches at thesideof Guide. in theInstallation Manual/Owner’s Additional information isprovided the tables that start onpage 25. altitude installations, refer to related to vent length orhigh- For specificDIPswitch settings section. positions are illustrated inthat page 25.Thecorrect DIPswitch Refer to “DIPSwitch Settings” on ngs on on 2. Check the High Limit Switch and ChecktheHighLimitSwitch and 2. debris. verify that thegas lineiscleared of gas appliancesare inoperation. specified supplypressure whenall does notdrop belowtheminimum in standby, andverify thegas pressure Overheat Cutoff Fuse 2.1 Turn o • • 2.3 2.2 30. and Pressure Drop” onpage “Checking theInlet GasPressure regulator’s manufacturer. See changes indirection. Refer to the installed ontheoutlet before any amount ofstraight pipeis may recommend that aspecific Note: Somemanufacturer’s line (ifinstalled) issized properly. vent limiter isinstalled); thevent (pay closeattention ifanindoor the manufacturer’s instruction application; that itisinstalled per that itissized properly for the installed, verify thefollowing: If asecond stage regulator is pressure regulator at thegas meter. It ispossiblethat there isafaulty step. occurs proceed to thenext show error code 711,ifthis step 3.Thewater heater may DO hearthem,go directly to gas solenoidvalves. Ifyou the “clunking” noisesofthe computer board.) Listen for (Use theswitch above the heater, thenturnitbackon. cord orexternal switch. by disconnec (item 412,p.74). Locate thehighlimitswitch Turn o 8 (p.41). Figure 21(p.40)andTable ff ff power to thewater power to theheater (OHCF) as f ng thepower

See also Also, ollows: ollows: . Checkfor asparkinsidethe burner 4. Checkfor blockages inventing, such 3. around. place, whileaweak sparkwilljump blue sparkwillremain steady andin igniter andflamesensor. Astrong the sight glasslocated next to the The sparkmay beviewed through chamber between theigniter rods. to maintain combustion. leading reduced capacity andinability blockage willcause improper operation as bird nests, animals,ortrash. A 2.3.2 2.3.1 2.3.3 . Ifnosparkora weak sparkis 4.1 high. temperature may betoo system, theincoming water water, suchasfrom asolar supplied withpre-heated water supply. Iftheunitis temperature oftheincoming Also, besure to checkthe the troubleshoo determined. Con the highlimittripmust be burner lights, thecause of and test theheater. Ifthe Turn thepower backon the bu reset ifyou heard andfelt middle ofit.Theswitch was Push thebu fuse (OHCF)for con check theoverheat cuto noises ofthegas valves, then don’t hearthe“clunking” opera If thehighlimitswitch is there isnocon igniter wire connec observed, checkthepurple 32. the OHCFfor con instruc Cuto to “CheckingtheOverheat ff Fuse(OHCF)”onpage ng properly andyou on click. ons onhowto test on inthe nuity, orfor ng process. nue with nuity, refer ons at nuity. If ff

TROUBLESHOOTING . If the Ω on Air and . Normal resistance for SV2 SV2 for . Normal resistance Ω resistance is out of range, replace replace is out of range, resistance valve. the gas 1.65 k is 2.07-2.53 k and SV3 Code 201: Combus Gas Line Failure is sensor • Check if the pressure functioning properly. is functioning motor • Check if the fan properly. of /breakage connection • Check for on the PCB. burn marks wires, Code 211: Air Pressure Sensor Failure the between • Check the voltage 6 Normal: 4 to wires. black and red (during black & red VDC between operation) sensor if the pressure • Replace is outside of the range. the voltage is within voltage the PCB if the Replace range. the normal voltage

. If the Ω resistance is out of range, replace replace range, is out of resistance valve. the gas turn do so, To solenoid valves. then check the off, the power A normal of the valves. resistance is 1.35- SV1 for reading resistance “Cleaning the Flame Sensor and “Cleaning the Flame 33. on page Rod)” Igniter the wiring Unplug both ends of assembly the igniter harness from then reconnect board, and control connection. good ensure them to that wire green the that verify Also, is attached is part of the circuit connections one of the screw to the manifold. around do so, (MV). To valve main gas then check the off, turn the power A normal of the MV. resistance k is 1.15-1.65 resistance LED stayed off, then inspect the then inspect off, LED stayed it if necessary. Clean flame sensor. (chips or damage it if any Replace or is seen ceramic) in the cracks freely move can rod if the metal See insulator. in the ceramic On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 17 7. 7. of the gas operation proper Verify 6. 6. of the operation proper Verify ll ons. ached and that If the previous steps s steps If the previous When the igniter is sparking,When the igniter the across check the voltage the to coming purple wires is Normal voltage igniter. is If voltage 108-132 VAC. then outside of this range, board. the computer replace 77 for 701 on page (See item part number.) the correct Check the igniter rod to to rod Check the igniter is the black wire sure make a properly If move. doesn’t the rod the replace moves, the rod will also need You rod. igniter holder gasket. a rod in a spark being don’t result the igniter. replace generated, both the igniter and at the and at both the igniter Unplug and board. computer clean the to them reconnect connec electrical 4.4 4.3 4.2 seconds before going out, verify out, verify going before seconds on IN USE LED the green that or remote controller the built-in If the did not turn on. controller 5. 5. 1-2 only on for If flame comes TROUBLESHOOTING Figure 4: Cleanthethermistor asfollows: 5. Checkthethermistor’s resistance 4. After you have located thecorrect 3. Identify therow inTable 3that 2. 1. detects athermistor failure. The system displays thiscode whenit Thermistor Failure Code 311,321,331,341or351: 18 • On-Demand Water Heater Handbookfor Service X3PModels

ZĞƐŝƐƚĂŶĐĞ;ŬɏͿ same temperature range. thermistors inapproximately the several minutes to get allthe water through theheater for normal resistance values. Run value. SeeFigure 4for alist of burns orcuts. connections are secure andfree of thermistor, verify that thewire instructions. applies to you, thenfollow its Turn offpower to thewater heater. 10.00 15.00 20.00 25.00 30.00 35.00 0.00 5.00

Temperature vsResistance Graph 23.76 ° ° 0C1° 0C2° 0C3° 0C4° 0C5° 0C6° 0C7° 0C8° 0C9° 100°C 95°C 90°C 85°C 80°C 75°C 70°C 65°C 60°C 55°C 50°C 45°C 40°C 35°C 30°C 25°C 20°C 15°C 10°C 5°C 0°C 2F4° 0F5° 8F7° 6F9° 0° 1° 2° 3° 4° 4° 5° 6° 7° 8° 9° 0° 212°F 203°F 194°F 185°F 176°F 167°F 158°F 149°F 140°F 131°F 122°F 113°F 104°F 95°F 86°F 77°F 68°F 59°F 50°F 41°F 32°F 30.04 19.08 24.12 15.43 19.50 12.56 15.87 10.28 13.00 8.47 Temperature vsResistance 10.71 7.02 8.87 . Iftheerror code persists, replace 7. Return thewater heater to service. 6. 5.85 Exhaust Thermistor 7.39 the thermistor. b. Drain theunitofwater. (See a. . Reinstall thethermistor. d. Cleantheprobe to asilver c. 4.90

6.19 Cleaning” onp.29.) Cleaning” “Unit Draining andFilter around thissensor. rubber o-ringthat wraps finish. Donotlosethered separate from theprobe. as you may cause thewire to base. Donotpullthewire out bygrabbing themetal then pullthesensorprobe that secures thethermistor, Remove thescrew orclip 4.12 5.21 3.49

4.41 2.96 3.74 Temperature Thermistor 2.53 3.19 2.16 2.73 .61.60 1.86 2.35 2.03 .912 .509 0.81 0.92 1.05 1.21 1.39 1.76 1.53 1.33 1.16 1.02 TROUBLESHOOTING . Ω gas solenoid valves for burns or for solenoid valves gas cuts. the proper installation altitude. installation the proper turn off is needed, If adjustment and adjust. the heater to power the error 4 for step to Then go If this heater. and test reset code 2-4. steps to doesn’t fix it, go fit. loose and/or blockage for debris or blockage any Remove the damper from keep would that rotating. (during & brown (white) COM Visual inspection of PCB: operation) and/ of wires connection/breakage on the computer or burn marks board. 10 of 991 error step Procedure, 24. on page code resistance of the valve. Normal Normal of the valve. resistance is 1.15-1.65 k reading resistance If the resistance is out of range, is out of range, If the resistance valve. the gas replace blue (blue - light wires valve gas The voltage #3) during operation. VDC. If should be 93-120 reading within normal is not the voltage board. the computer replace range, Code 551: Abnormal Solenoid and/or SV2, (SV1, Gas Valve SV3) a driving circuit indicates This code of the solenoid one or more for fault or SV3). SV2, (SV1, valves gas 1. the to connections Check the wire 2. serviced recently If the unit was Code 521: Air Damper Failure Code 521: Air Damper 1. for set are the DIP switches Verify 2. of the air damper Visual inspection 3. 11 VDC between Normal: 3 to 4. Reset to go code, this error reset To 6. 6. the main across Check the voltage

flames are still visible through the visible through still flames are immediately window, burner sight the unit to and power gas shut off service the technical and contact department. burns or cuts. for valve main gas be had to valve and the gas each gas that sure make removed, the is fully plugged into wire valve connector. is within the specified limits. An high is too that pressure gas inlet the main gas jam or damage can valve. wires to see if they are broken or broken are see if they to wires disconnected. select do so, To controller. heater’s INFO by pushing the Flow Rate the left on the arrow until button toward points side of the display the controller that Ensure “Flow.” during rate a flow displays is not If a flow rate operation. step. the next to proceed indicated, debris. then heater, the to power electrical the flow sensor/control remove (p. 61). Check the flow valve sensor as described in “Checking 32. Clean page the Flow Sensor,” as necessary. or replace On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 19 This code indicates a fault in the main a fault indicates This code (MV) circuit. valve gas 1. but is shut off, If the hot water 2. the to connections Check the wire 3. serviced recently If the unit was 4. supply pressure gas the that Verify 5. check the off, With the power Code 511: Abnormal Main Gas Code (MV) Valve 4. 4. valve sensor/control Check the flow 5. the water using the flow rate Verify 6. for filter Check the inline water 7. supply and the gas off Turn return connection and clean connection return as necessary. in the pump debris any and clean as connections needed. the sure make check to DIP switch valve crossover is in the ON position setting bank). #5, top (DIP switch • on the Inspect the filter • for Inspect the pump • valve, If using a crossover should be operating, then: should be operating, before system the linked from 2. The water step to advance you as an be tested must heater individual unit. turned on. a socket that is properly grounded. grounded. is properly that a socket this cause can ground A floating error. of burns or cuts. and free secure is wire ground the green that Verify and is making an properly installed This ground connection. electrical the to is part of the connector wire to is secured wire PCB. The green the of the right to plate the metal box. surge (Flame Sensor Assembly the Rod 33. on page Rod)” and Igniter Code 441: Flow Sensor Failure 441: Flow Sensor Failure Code when the is displayed This code a signal from doesn’t detect computer the flow sensor when the pump is in the Easy- running or when a heater is running. Link System 1. when the pump appears If the code 2. heater the water Disconnect 3. is supply the water that Ensure Code 391: Flame Rod Failure Failure Flame Rod Code 391: 1. is plugged the unit into that Ensure 2. are connections the wire Check that 3. See “Cleaning rod. Clean the flame TROUBLESHOOTING . Checkthevoltage across these 5. 20 • On-Demand Water Heater Handbookfor Service X3PModels Checkventing for blockages orfor 2. Disconnect power to thewater 1. This code indicates afan motor fault. Code611:AbnormalFan Motor Withthepower off, checkthe 4. Verify that thesupplygas pressure 3. common.) operation. (Thedarkbluewire is solenoid gas valve wires during replace thegas valve. If theresistance isoutofrange, for SV2 andSV3 is2.07-2.53k heater cabinet. Correct any issues no contaminants inside thewater dust). Make sure that there are the water heater area lint, (e.g., the presence ofcontaminants in circuit breaker. wall outlet orturningitoff at the heater itfrom byunplugging the 1.65 k resistance reading for SV1 is1.35- resistance ofeachvalve. Normal could bedamaged. cause themaingas valve to jamor high ofaninlet gas pressure may is withinthespecifiedlimits.Too printed onthewire’s label. must match thenumberthat is the numberstamped onthemetal proper place.(For eachconnector, gas valve wire into isplugged the removed, make sure that each and thegas valve hadto be replace thecomputer board. voltage isnotwithinnormalrange, should be93-120VDC.Ifthe In eachcase, thevoltage reading • • • SV3: Red (#73)&Blue SV2: Orange (#53)&Blue SV1: Green (#9)&Blue Ω . Normalresistance reading Ω . 3. Inspect the pump for buildup or debris Inspectthepumpfor buildupordebris 3. Checkthefilter onthereturn 2. Verify thecheck valve isoperating 1. Code 631:PumpFault . Complete thisstep onlyiftheprevious 7. Turn onpower to thewater heater, 6. Checkthefan housingfor water. 5. Checkfor leaks at theheat 4. Visuallycheckfor breakages inthe 3. connection andcleanasnecessary. pump. water moves backwards through the properly. Thiscode appears when 28.) “FM” inthewiringdiagram, page below. Thebluewire iscommon. (See between thefan motor wires listed During operation, checkthevoltage steps didnotsolve theissue. then test theheater. exchanger. replace asneeded. the computer board (PCB).Repair/ fan motor wiringorburnmarks on that are found. If thevoltage readings are normal range, replace thefan motor. If thevoltage readings fall withinthe • • • board. normal range, replace thecomputer (during operation) Normal: 2to 6.5VDC Orange &Blue (during operation) Normal: 13to 17VDC Yellow &Blue (during operation) Normal: 132to 192VDC Red &Blue not within within . Complete thisstep onlyiftheprevious 5. Inspectthewires to thepumpfor any 4. . Inspecttheflow adjustment valve 1. valve fault. This codeindicatesaflowadjustment Fault Code 651:FlowAdjustment Valve 28.) inthewiringdiagram, page “PUMP” The bluewire iscommon. (See between thepumpwires listed below. During operation, checkthevoltage steps didnotsolve theissue. they are compromised. cuts orbreakage. Replace thewires if the pumpisnotairlocked. the debris.Oncere-installed make sure speed ofthepumpimpeller. Cleanout in theconnections that can reduce the following: (item number402,p.73)for the range, replace thecomputer board. voltage readings are normal range, replace thepump.If If thevoltage readings fall withinthe • • • • • • (during operation) Normal: 132to 192VDC Red &Blue seals/component.) adjustment valve (Replace the Water leakage at theflow the valve from openingorclosing valve assemblythat would prevent Debris orscale buildupinsidethe Broken ordisconnected wires (during operation) Normal: 1.0to 6.5VDC Orange &Blue (during operation) Normal: 13to 17VDC Yellow &Blue not within normal within normal TROUBLESHOOTING erence erence ff ) ve degrees, degrees, ve fi Circuit is Fuse ff See page 28 See page

of more than of more Code 311, 321, 331, to refer 341 or 351: Thermistor p. 18. Failure, finished, are When you heater. the water retest thermistor. The readings The readings thermistor. similar and it should be the reading should be supply of the temperature is a di If there water. to “Code 111 or 121: Ignition “Code 111 or 121: to See on page Loss,” / Flame Failure 16. “Checking to Refer compromised. Fuse (OHCF),” Cutoff the Overheat 32. page Refer fault. valve gas (PCB) and/or 510 and 551. codes error to the high limit switch, the OHCF, the OHCF, the high limit switch, to breaks any for valves and the gas or cuts. valve main gas the to connections the PCB and the gas to next located assembly located solenoid valve (For exchangers. the heat above the number each connector, match must the metal on stamped on the is printed the number that label. wire’s 3. 3. Refer Check the High Limit switch. 4. be may switch Cutoff The Overheat 5. board be a computer may There Compromised Code 711: High Limit Switch / Limit Switch Code 711: High Overheat Cuto the to is turned on When power a performs the computer heater, valve, check of the gas diagnostic Fuse Cutoff high limit, and Overheat are of these If any (OHCF) circuits. will appear. this code compromised, 1. wire blue common Inspect the dark 2. wiring harness proper Verify

See . If on on on Ω on on on mes. bu ff . ff connector #715 on page 73. #715 on page connector Run water through the through Run water heater. of Check the reading by thermistor the outlet bu pushing the INFO the temperature/remote two controller the inlet it to Compare Unplug the bypass valve’s bypass valve’s Unplug the ina connector is harness. There of the harness whichthe middle access by removing can you The board. the computer red, are colors harness’ wire blue, brown). white, yellow, between Check the resistance (You wires. and red the brown the female use the pins in can Normal resistance connector.) 85 50 to (brown-red): is out of range, the resistance the bypass valve.replace the temperature controller controller the temperature so the controller or remote LED turns BY STAND orange o 2.2 2.3 2.3 2.2 2.1 Push the on/o for connection/breakage of wires of wires connection/breakage for burn marks. and/or as follows: thermistor To check it, measure between the between check it, measure To #715 (Connector wires. and red brown range 73.) Normal voltage on page (brown-red): is out3 VDC - 11 VDC. If the voltage board. the computer replace of range, 73.) (See page On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 21 This code indicates a computer board or board computer a indicates This code fault. thermistor outlet 1. (PCB) board Inspect the computer 2. of the outlet Check the operation 3. 3. of the bypass valve. Check the voltage Board 701: Computer Code Fault ow fl ow adjustment ow . If the resistance is. If the resistance fl Ω the to power electrical the to power electrical ff ff heck the resistance between heck the resistance urn o urn o adjustment valve. valve. adjustment the red and black wires. and black wires.the red (black-red): Normal resistance 200 90 to the replace out of range, C Unplug the valve’s connector from the from connector valve’s Wiring (See board. computer 28.) on page Diagram water heater, then. heater, water water heater, then. heater, water Locked motor drive due to debris due to drive motor Locked build up inside the valveor scale assembly the bypass valve at leakage Water Broken or disconnected wires or disconnected Broken look behind the fuse box to (Be sure assembly fromand check the wire red, colors: Wire the bypass valve. blue, brown.) white, yellow, 2.1 T • • • 2.3 2.2 2.1 T adjustment valve where its connector where valve adjustment between the PCB. Measure plugs into 20 (See page wires. the black and red (black- range or 20.) Normal voltage red): is out7 VDC - 16 VDC. If the voltage board. the computer replace of range, 28.) (See page valve. To check it, To valve. 403) for the following: 403) for adjustment valve. To check it, To valve. adjustment 3. 3. of the flow Check the voltage 2. 2. of the bypass Check the resistance This code indicates a bypass valve fault. a bypass valve indicates This code 1. number (item Inspect the bypass valve Code 661: Bypass valve faultCode 661: Bypass 2. 2. of the flow Check the resistance TROUBLESHOOTING . Verify that onlyasingleremote 2. Verify that theremote iscompatible 1. NOTICE: for indoormodels. associated withthebuilt-in controller the water heater. Thiscode is temperature remote controller and miscommunication between the This code indicates a Problem Code 741:Remote Control 1. system stopped theignitionprocess. should have beenpresent, sothe system duringstart up.Noflames A false flamewas detected bythe Detec Code 721:False Flame . Inspecttheflamesensorto 2. 22 • On-Demand Water Heater Handbookfor Service X3PModels remote from theheater. off power before disconnecting the on, thiserror code willresult. Turn the heater withthepower supply If you disconnect theremote from code. remotes willresult inthiserror An incorrect remote ormultiple built-in temperature controller. may beusedinadditionto the is installed. Onlyoneremote heater’s installation manual. remote’s instruction sheet andthe with thewater heater. Refer to the WARNING! further assistance. technical department service for Igniter Rod, p.33.Contact the Cleaning theFlameSensorand the assembly, ifnecessary. See ceramic housingfor cracks. Clean see ifitisdirty. Also, checkthe personal injuryordeath. so couldleadto fire, explosion, power to theunit.Failure to do on

Shut offallgas and not . Checkthevoltage across the 3. Power surges can cause thisfault. If 2. Checkthat allwiringisproperly 1. associated withtheremote controller. controller. heater andthe miscommunication between thewater This code indicates a Controller Code 751:Temperature Checkthevoltage across thewires 5. Power surges can cause thisfault. If 4. Make sure that allwiringis 3. computer board (PCB). voltage isoutofrange, replace the in temperature controller. Ifthe normal range, replace thebuilt- be 11VDCand17VDC.Ifwithin remote. Normalvoltage should wires that are connected to the nuisance faults. adequate surge protection to prevent frequent power surges occur, install temperature controller. connected to thebuilt-in (PCB). range, replace thecomputer board remote. Ifthevoltage isoutof within normalrange, replace the voltage shouldbe11-17VDC.If coming to theremote. Normal nuisance faults. adequate surge protection to prevent frequent power surges occur, install properly. connected to theremote controller NOTE: Problem Problem built-in Thiscode is temperature not in Easy-Link System . Verify that theheater in question 2. Inspectthewiringbetween the 1. To address thiserror, dothefollowing: heater’s power off andthenbackon. the easy-link wires orcycle theparent To reset thecode, eitherreconnect heater inanEasy-Link system. This code willdisplay ontheparent communication withat least oneheater. unit intheEasy-Link system haslost A 761error code meansthat theparent Code 761:Communica during different phasesofoperation. These codes are related andappear Code 051and101) or Exhaust GasBlockage (also Code 991:Combus link system. to remove thisheater from theeasy- parent heater’s power off andthenon heater to troubleshoot, thencycle the disconnected theeasy-link wire to a If theerror appeared whenyou has power to thecomputer board. identified bythecode. Parent heater andtheheater • • • • • computer board ison. Make sure theswitch above the Code 101:Thiserror code will hour timeperiod. This checkoccurs onceina 24- during thepost purge sequence. air and/or exhaust vent issues appear ifthere are combustion Code 051:Thiserror code will water heater inquestion. Verify proper supplypower to the blown. absorber inthefusebox hasnot Make sure that afuseorsurge on Airand/ on Error TROUBLESHOOTING on MIN MAX erence erence onal Fuel onal ff ed limits when fi greater ring is fi INCREASE DECREASE by B149.1. ed open and MAX ple taps on of the Na the heater is in standby is in standby the heater and when it is running with mul on the computer pressed board? and standby between maximum the supply than 1 inch W.C., and/or meter, line, gas be undersized. may regulator In Canada, do not NOTE: the maximum exceed drop pressure allowable permi lines the gas that Verify the correct for sized are Gas NOTE: of gas. volume based will vary line capacity line material on type of gas the installa to used. Refer Is the gas supply pressure supply pressure Is the gas within speci di If the pressure manual or the current edi Gas Code, ANSI Z223.1/ Gas or Natural 54 (U.S.) NFPA Code, B149.1 and Propane (Canada). NOTE: Do not proceed to the to Do not proceed NOTE: this one has until step next and these been completed been ruled out. have causes venting, installed Improperly settings, DIP switch incorrect Checking Combustion Status. Checking Combustion

8.3 8.1 8.2 Figure 5: Figure 8. following: Check the . above above . on? The water your ng for higher are ons that vent manual for on 26. on page ngs” 90-degree ngs. Each than 2,000 feet above sea above than 2,000 feet “DIP Switch to Refer level. Se requirements. requirements. sea level or less. A DIP sea level for is required change switch installa heater is 2,000 heater Is the heater set to the to set Is the heater eleva correct se default elbow is equal to 5 feet of 5 feet to elbow is equal the to pipe. Refer straight installa se Fan motor intake motor Fan Air intake and exhaust Air intake screen tray Rain protection • • • 3.2 any breakage and/or burn marks on burn marks and/or breakage any the PCB. air lines. Clear them if any or intake Check the following: found. are the minimum clearances that that the minimum clearances outlined in the installation are (Doing so codes. manual and local flue gas the risk of will minimize no that ensure Also, recirculation.) gasses exhaust other appliance’s the intake. be pulled into can cabinet heater’s inside the water on the fan and inside the fan and cabinet blades. Clean the fan also It may debris is present. if any debris inspect for be necessary to of the burners or a partial blockage the flame quality. affect could that On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 23 4. 4. for wiring connections Check for 5. in the vent obstructions Check for 6. 6. meet the terminations that Verify 7. air signs of contaminated Check for . ving, Replacing, This water heater’s gas heater’s This water the correct ngs, p. 25 for Familiarize yourself with yourself Familiarize Are the DIP switches set for for set the DIP switches Are and size vent the correct DIP Switch to Refer length? Se NOTE: NOTE: appear if there are combustion combustion are appear if there issues vent exhaust air and/or sequence. pre-purge during the will code Code 991: This error combustion are appear if there issues vent exhaust air and/or operation. during heater 3.1 • the gas type of the water heater heater of the water type the gas the type applied to the gas matches unit. the confirm type is field convertible, type the gas matches orifice installed supplied. See Remo the Gas Orifice and Verifying make 47. Next, Assembly on page DIP switch the gas-type that sure 5 on (See Table is correct. setting 27.) page specified in the requirements manual (e.g., vent installation and length). diameter the components before attempting attempting before the components the Installation Use these procedures. the component Manual and reference of the pages few on the last schematic manual. must procedures These first! Safety by licensed, qualified be performed to Failure only. service professionals lead to could observe this warning injury or death. personal is not liable for The manufacturer if he/ the actions of the technician or all safety any to adhere to she fails to in regards specifically procedures, safety. and gas electrical 1. that verify to plate Check the rating 2. the meets the venting that Verify 3. settings. the DIP switch Verify WARNING! WARNING! TROUBLESHOOTING 24 • On-Demand Water Heater Handbookfor Service X3PModels 10. Reset Procedure Contact Technical Support 9. code: to clearthe101/521/991error Complete thefollowing procedure correct values, ifnecessary. adjust themanifold pressure to the approval from Technical Support, (See Table 1onpage 4.)With regarding themanifold pressure. 10.6 10.5 10.4 10.3 10.2 10.1 manifold pressure readings. venting orheater and obstructions inthe above thecomputer board. opera in standby andready for to placethewater heater O power on.Press theOn/ A using theon/o Shut o back o The green LEDwillthenturn computer board turnson. the green LEDonthe Release thebu page 30.) seconds. (SeeFigure 11on DECREASE bu hold theINCREASE and simultaneously press and On thecomputer board, standby light iso controller sotheamber the remote/temperature Press theon/o heater ispowered on. Make sure that thewater ff er 5seconds, turnthe bu ff on. ff on thecontroller

power to theheater .

ons for ff ff bu switch ons when ff will . on on affect fi ve ve TROUBLESHOOTING Upper Bank Middle Bank Lower Bank ƉŽƐŝƟŽŶ ve (Default) OFF ĐƟ (Default) (Default) (Default) DIP switch location. location. DIP switch

Figure 6: Figure ve ƉŽƐŝƟŽŶ

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1 2 No. 3 pump opera Interval 5 installa valve over Cross 6 7 8

4 Pump opera DIP SWITCH SETTINGS SETTINGS SWITCH DIP Table 3: Table Upper Bank of DIP Switches If you have questions, contact the technical service department. NOTE: Dark NOTE: service department. the technical contact questions, have If you position. DIP switch represent squares Verify the functions of each DIP switch carefully before changing any settings. settings. changing any before carefully DIP switch the functions of each Verify off. the heater to power with the supply DIP switches Only adjust The computer board layout for all models is identical. See “Wiring Diagrams,” See “Wiring Diagrams,” identical. all models is for layout board The computer on the functions as shown special certain have 28. The DIP switches page need adjustment. should not and generally tables following TROUBLESHOOTING Middle BankofDIPSwitches Table 4: 26 • On-Demand Water Heater Handbookfor Service X3PModels DIP SWITCH SETTINGS Parent se 1 No. Outputtemperature se 5 4 3 2 N AOFF 6N/A &ƵŶĐƟŽŶƐ ůƟƚƵĚĞĂĚũƵƐƚŵĞŶƚƐĞƫŶŐƐ (0 to 610m) 0 to 2,000 (Default) ON ƫŶŐ 123456 Ō for Easy-Link System 2,001 to 3,000 (611 to 914 m) ON Parent (60 °C) 140 °F

ON 123456 Ō ON

123456 ƫŶŐƐ 123456 3,001 to 1,524 m) 5,000 (915 to ŝŶƐ

S (Default) (Default)

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123456 Ō 10,100 7,501 to (2,287 to 3,078 m) ON

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TROUBLESHOOTING

12345678 ON ve ƉŽƐŝƟŽŶ ve (on) ve /ŶĂĐƟ (Default) ĐƟ (Default) OFF (Default) ϱƚŽϵ͘ϵŌ ϱƚŽϱϵ͘ϵŌ ϱƚŽϱϵ͘ϵŌ ϱƚŽϭϰ͘ϵŌ sĞŶƚůĞŶŐƚŚ /WƐǁŝƚĐŚĞƐ ) (1.5 to 3.0 m) (1.5 to 4.5 m) (1.5 to 18.3 m) (1.5 to 18.3 m) ī ϮΗĞůďŽǁ͗ϱŌ;ϭ͘ϱŵͿ ϮΗĞůďŽǁ͗ϱŌ;ϭ͘ϱŵͿ ve (o ƉŽƐŝƟŽŶ ve KƵƚĚŽŽƌŝŶƐƚĂůůĂƟŽŶ type Vent Intake Intake Intake Intake džŚĂƵƐƚ džŚĂƵƐƚ džŚĂƵƐƚ džŚĂƵƐƚ ĐƟ /ŶĂĐƟ ON

Vent style 3" PV 2" PV 2" DV 3" DV

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On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 27

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type Vent ĞĐƟŽŶ Intake Intake Intake Intake džŚĂƵƐƚ džŚĂƵƐƚ džŚĂƵƐƚ džŚĂƵƐƚ ƫŶŐƐ style Vent 2" PV 3" PV 2" DV 3" DV Gas type Vent se &ƵŶĐƟŽŶƐ N/A OFF

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Table 5: Table of DIP Switches Bank Lower DIP SWITCH SETTINGS SETTINGS SWITCH DIP TROUBLESHOOTING WRN DIAGRAM WIRING 28 • On-Demand Water Heater Handbookfor Service X3PModels maintenance sheet isstored inapouchontheinsideofwater heater’s front cover. For instructions onhowto use checkpoints refer duringtroubleshooting, to thewater heater’s maintenance sheet. The Figure 7: Air damper

Thermostat Thermostat O.H.C.F Heater limit Hi- SV2 MV SV3 SV1

131 Wiring Schematic for 160X3P, 180X3P, and199X3PModels Heater 721 BR BR BL BK BK BL BL BL BL LB BL BK BK R R G Y Pump B O FM Valve y Y Y W BL BL p BK a s BL s BR LB Y R G Y Y BR W Igniter BL rod BR W O BL R R BL O Adjust Y Valve W Flow Y R R Y Y W Y Y Heater Heater Heater Heater Y O 715 IG 103 R BR W 738 Y BK BK BL R 737 Y P P 715 Surge box W 73 53 Ground BK 9 BK P P BK W R W 708 715 BK SW Ground

BR 708 Wireless G R BK W G O 715 Y G BL 714

W

BK Monitoring 120 VAC G BL 715 Y 709 Y G R Flame rod 715 W ༃༄ Easy-Link LB: LIGHTBLUE BK: BLACK W: WHITE BK Ground BK 715 R W BK W

715 Parent W 715 BK P: PURPLE R: RED G: GREEN BK 715 R R KBK BK W W KBK BK BK BK BK BK BK BK 722

Sensor Flow ON ON ON BL: BLUE :OAG BR:BROWN O: ORANGE

1 23456 78 123456123456 78 R W R W Exhaust thermistor WW BL BK Inlet thermistor Outlet thermistor Heat exchanger Return thermistor thermistor MIN button DIP switches Decrease button MAX button Increase button Pressure Sensor controller Built-in Remote controller Y: YELLOW Y:

SERVICE PROCEDURES Drain plugs must be hand be hand must plugs Drain valves. valves. NOTICE: only. tightened 8. 8. all drain plugs and close all Replace With a small brush, With a small brush, The filter strainer basket can can basket strainer The filter Cleaning the filters. Cleaning the Drain plug removal. Drain

Clean the filter. clean the water filter of any debris of any filter clean the water (See accumulated. have which may is clean, 9). When the filter Figure it. reinstall On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 29 Figure 9: Figure NOTICE: threads. the filter from be separated the that be sure When separated, and is in place before O-ring is not lost the filter. reinstall you Figure 8: Figure 7. When

Cleaning

WARNING

power to the unit again. to power the water catch plug to filter/drain the also drain may You when it drains. the outdoors. to water filter. and the water

the water flow stops, close all hot flow stops, the water faucets. water Filter/Drain Plugs Plugs Filter/Drain 4. 4. faucets. Open nearby hot water 2. 2. OFF then turn 30 seconds, Wait 3. valve. shutoff water Close the cold plugs 6. drain filter the water Remove 1. valve. shut off gas Close the manual 5. or pan under the water Place a bucket Water drained from the water heater heater the water from drained Water severe and could cause be hot may observe proper to burns. Failure serious could lead to practices safety injury. personal SERVICE PROCEDURES PROCEDURES SERVICE SERVICE PROCEDURES 30 • On-Demand Water Heater Handbookfor Service X3PModels Ifwater continues to runthrough 3. Openthepressure-relief valve or 2. Closecold water supplyat theinlet 1. Turn onhotwater at 2. Turn off cold water supplyvalve 1. the pressure-relief valve orhot faucet. the hotwater tap ofatwo handle and pumpreturn connections. the hotsideonly. fixture, make sure that itisopento If you must useasingle-handle hot sideofatwo-handle fixture. the structure. Ifpossible,usethe turned off. recirculation, ensure that they are pumps installed inthesystem for to thewater heater. Ifthere are • • • to bereplaced. single-handle faucet that needs application, oracartridge ina a missingcheckvalve inthe mixing valve, abadcheckvalve, pump application, adefective may berelated to arecirculation Cold water cross-connections need to bechecked. fixtures andplumbingsystem If water continues to run,the should drain completely. After abrief time,thewater Cekn for Checking for Checking Connec Connec a Reversed a Crossed one on on fixture in . Opensomeofthehotwater 8. Turn power to thewater heater on. 7. Slowlyre-open themanualgas 6. Connectamanometer to thepressure 5. Figure 10: Remove thescrew from the 4. Turn power to theheater off by 3. Openahotwater fixture. The unit 2. Closethemanualshutoff valve at 1. appliances onthesupplylineare operating. This test ismost effective whenallgas Cekn te Inlet the Checking Gas Pressure and reversed connection. water faucet, thesystem hasa heater hasreached asteady firing rate to turnontheunit.Once fixtures that usethehighest flow leaks. valve. Confirm that there are nogas port andzero themanometer. inlet. See Figure 10. pressure portlocated onthegas shutoff switch. itorclosingtheexternal unplugging extinguishes. when theflameinheater out. Closethewater fixture gas inthepipelineshouldpurge should turnonandtheremaining the gas supplylineinlet. Pressure Drop

Pressure portlocation. Pressure port 12. Record11. your gas supplypressure (static). 10. R Record your gas supplypressure 9. Figure 11: 17. T 16. Inst 14. If 13. Subtr 15. Remove 15. Remove within thefollowing ranges: The gas supplypressures should be close allofthewater fixtures. (dynamic). (See Figure 11). onthecomputer board button rate, severe injury, ordeath. leaks can result inanexplosion, no gas leaks. Failure to prevent gas WARNING! port onthegas inlet (handtight). gas regulator. sized gas line,orincorrectly sized insufficient gas supply, incorrectly than 1.5inchW.C., there may be be your pressure drop. supply gas pressure (step 11).Thiswill pressure (step 9)from your static by B149.1. allowable pressure drop permitted do notexceed themaximum • • urn power to thewater heater on. elease the“MAX” button and the pressure drop ismore Propane: 8to 13.0inchesW.C. Natural Gas:3.5to 10.5inchesW.C. all thescrew into thegas pressure

act your dynamic supply gas act your dynamicsupplygas Max button oncomputer board. press andholdthe“MAX” the manometer. Ensure that there are DECREASE INCREASE NOTICE: InCanada, MAX MIN . SERVICE PROCEDURES

Table Table MIN MAX ted in ted to remove the remove to TM INCREASE DECREASE Complete the following the following Complete Max button on computer board. on computer button Max

Pressure ng Manifold the manifold pressures do not do pressures the manifold adjusting port cover. See Figure 12. See Figure port cover. adjusting supply to on, then turn on the gas the manual gas at heater the water valve. shutoff operation. activate to or more) a draw you that It is suggested prevent of flow to amount large 1 on page 4, adjust the manifold the 4, adjust manifold page on 1 the to refer do so, To pressure. procedures. following 2. step to proceeding section before When you are finished, turn off finished, turn off are When you power then turn off flow and water heater. the water to valve, shutoff the manual gas at heater the manometer removing before the port screw. tube. Then replace ONLY step the next Complete to instructed been have if you Service the Technical do so by Department. up with those lis match 12. IF 3. 3. heater the water to power Turn 4. 3.5 GPM (preferably Run water Adjus WARNING! been have if you ONLY procedure do so by the Technical to instructed Service See WARNING Department. the beginning of this section. at text 1. 1 - 6 in the previous steps Follow 2. Use a T15 Torx Figure 13: Figure 10. the water supply to the gas 11. Shut off port (See ĚũƵƐƟŶŐ To manometer Manifold port location. port location. Manifold

Tube Port Check the manifold pressure pressure Check the manifold during minimum combustion, hold the “MIN” button and press board on the computer 13). Figure in listed are pressures The desired section. (See the “Specifications” 4.) page 1 on Table Silicone Manifold heater at the manual gas shutoff valve. shutoff gas the manual at heater • • manifold port (See Figure 12). (See Figure port manifold using a tube. Ensure port manifold secure is this connection that leak. a gas prevent enough to supply to on, then turn on the gas the manual gas at heater the water valve. shutoff operation. activate to or more) a draw you that It is suggested prevent of flow to amount large during maximum overheating leak is of a gas burn. If presence the shut off immediately detected, unit and inspect the tube/manifold to Otherwise, proceed connection. step. the next On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 31 4. the water supply to the gas Shut off Figure 12: Figure 5. the from the screw Remove 6. the to Connect a manometer 7. heater the water to power Turn 8. 3.5 GPM (preferably Run water 9. pressures: gas Check the manifold ving, This water NOTE: NOTE: closing the external ng the the ng Firing Rate Pressure and Pressure Manifold Gas Manifold Adjus WARNING heater’s gas type is field convertible, gas heater’s matches the orifice installed confirm type supplied. See Remothe gas Replacing, and Verifying the Gas and Verifying Replacing, 47. Orifice Assembly on page or by unplugging it switch.shutoff pressure and pressure drop, before before drop, and pressure pressure with this procedure. proceeding be will not pressures Manifold and if supply pressure set properly outside allowable are drop pressure tolerance. and altitude. Incorrect length vent will cause settings DIP switch readings. improper 3. 3. off heater the water to power Turn 2. 2. for settings DIP switch proper Verify 1. 1. supply gas proper verify must You Checking the Manifold Gas the Manifold Checking Pressure NOTICE: damage may adjustment Incorrect shorten and/or heater the water changing Therefore, its lifespan. is not pressure the manifold very are unless there recommended do so (e.g., to high reasons strong installations). elevation Complete the following procedures procedures the following Complete been instructed have you if ONLY Service the Technical do so by to adjustment Incorrect Department. monoxide in carbon result may poisoning. SERVICE PROCEDURES 32 • On-Demand Water Heater Handbookfor Service X3PModels 1. Press andhold downthe“MIN” 5. 10. V Turn power to thewater heater 9. After thegas pressure hasbeen 8. Shutoff thegas supplyto the 7. Whenyou are finished,turnoff 6. Overheat Cuto electrical shock. Failure to dosocan result in the water heater before servicing. Disconnect electrical power from Use theT15Torx Figure 13. button onthecomputer board. See the next step connection. proceed Otherwise, to unit andinspectthetube/manifold detected, immediately shutoff the burn. Ifpresence of a gas leakis overheating duringmaximum shutoff valve. the water heater at themanualgas on, thenturnonthegas supplyto Figure 12. screw andadjusting portcover. See and re-install themanifold port set, remove themanometer tube, manometer tube. shutoff valve, before removing the water heater at themanualgas to thewater heater. water flowandthenturnoff power the desired value. verify that pressure hasbeenset to pressure. Usethemanometer to counter-clockwise decreases the clockwise increases pressure and the manifold pressure. Turning erify proper operation. Cekn the Checking Fuse (OHCF) WARNING TM driver to adjust ff

. Locate thewhite OHCFwhichwraps 2. . Restore power andtest theunit. 6. Test resistance at theendof 5. Unplugtheconnection. 4. Findthewhite clipat theendof 3. Figure 14: 14). around theheat exchanger (SeeFigure burn marks, hot spots,cracks, etc. Inspect theheat exchanger for any Procedures”the “Service section. instructions whichare found in “Replacing theHeat Exchanger” the heat exchanger. Follow the part willrequire you to remove replace theOHCF. Replacing this If theresistance exceeds 1ohm, or less.Reconnect theplug. Resistance shouldmeasure 1ohm OHCF withadigital volt/ohm meter. from theOHCF. the two bluebraided wires coming KǀĞƌŚĞĂƚƵƚŽītŝƌĞƐ

Oeha cutoff. Overheat (Blue) . Reinstall theflowsensoras described 5. ● ● Tools andMaterials: . Blowinto theinlet oftheflow 4. Remove theflowsensor#402 3. Turn off cold water supplyvalve to 2. You can checktheflowrate by 1. To checktheflowsensor, spins aswater runsthrough it. rate isdetermined byanimpellerthat located above theX3Manifold. Itsflow is partoftheflowcontrol valve and The flowsensor(item 402,p.73) Checking theFlow page 61. Water PipingSystem Components”, in “Removing and Replacing the control valve. replace theflowsensor/flow impeller doesnotmove freely, that cannot beremoved, orifthe the flowsensor. Ifthere isdebris NOTICE: inspected for blockage. or doesn’tspinat all,itshouldbe seconds. Ifitcomes to rest abruptly spins. Itshouldspinfreely for afew sensor. Watch to seeiftheimpeller Components”, page 61. Replacing theWater PipingSystem as describedin“Removing and the water heater. sensor isworking properly. This willdisplay flowifthe the built-in controller three times. heater. Pushthe“Info” button on turning onpower to thewater Towels Flashlight Do nottryto disassemble Sensor SERVICE PROCEDURES cover. Be sure to connect all 3 connect to Be sure cover. of the burner. on the front wires make to all gaskets inspect Also, debris of free are they that sure If the not ripped or torn. and are replace ripped or torn, are gaskets reassembly. them BEFORE 7. 7. operation. proper Verify on or on n n o on of the r C Clean on points. so of the burner. n Se clean the external clean the external

e inside Be careful to not drop or not drop to Be careful glass. lose the sight The flame sensor is of the rest from separate the assembly. m that extends to the to extends that la Flame Sensor Connector F or other wool ne steel or igniter ame sensor rod flame sensor and igniter flame sensor and igniter rod Use inside of the burner. fi Be sure abrasive. suitable oxida any remove to contaminates. Do not fl connec rod on extensions only the metal the Remove the four Phillips- the four Remove holding the head screws panel in place. Pull the assembly out. NOTICE: • • Removing flame sensor connector. sensor connector. flame Removing

5.2 5.1 Clean the por 3.3 3.4 chips or cracks. (These ceramic (These ceramic chips or cracks. holds the flame sensor insulators in place.) rods and igniter are chips or cracks it if any Replace freely moves visible or if either rod inside the ceramic. as described. rod and metal rods, gasket, order: Press small Press tab. On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 33 4. 4. for insulators Inspect the ceramic 5. sensor and igniter Clean the flame 6. the unit in reverse Reassemble Figure 16: Figure ons in ons The yellow wire wire The yellow ve spade. To release release spade. To ve Rod ame sensor connector, ame sensor connector, fl

Figure 16. Figure is locked onto the rod’s the rod’s onto is locked conduc the the instruc follow Disconnect these wires. Disconnect NOTICE: green wires located in the located wires green of the unit (beside the center glass). sight Igniter Rod/Flame Sensor Cleaning Rod/Flame Igniter

Flame Sensor/Igniter Rod Assembly Rod Flame Sensor/Igniter #2 Philips Screw Driver #2 Philips Screw gasket Replacement Fine steel wool or other suitable or other suitable wool Fine steel abrasive 3.2 3.1 and grey the yellow, Locate described below. described below. heater by unplugging it from the by unplugging it from heater the at or turning it off outlet wall as appropriate. breaker, circuit using a volt is off power that Verify device. or similar meter and on the top screws on by two on the bottom. screws two

Sensor and Igniter and Igniter Sensor Cleaning the Flame the Flame Cleaning Figure 15: Figure 3. as assembly the rod Remove ● ● Tools: ● 1. the water to power Disconnect 2. It is held cover. the front Remove SERVICE PROCEDURES Figure 18: 34 • On-Demand Water Heater Handbookfor Service X3PModels should leave thisDIPswitch inthedefault OFFposi must bedesignated thePARENT unitbyturningONDIPswitch 1ofthemiddlebankasshownin more detailed installa heater can beconnected to thesameoraspeci 180X3P and160X3Pare notcompa an easy-link system of540Hheaters. The Note: The199X3Pmay beinstalled inwith The Easy Linksystem manages mul DIP Switch Se and theinstalla with any othermodelasnoted inTable 6 Connectors

1 2 3 4 5 6 UNIT PARENT ON

Multiple childunitconfiguration. OFF

DIP switches Middle bankof

1 2 PARENT on manual. ng Easy-Link ontheComputer Board ayLn Connec Easy-Link on instruc Controller TM-RE43 Remote Controller Built-in ons. ple water heaters to provide aset water temperature basedondemand/ ble ble oncosConnectors Connectors 1 2 3 4 5 6 ON 1 CHILD UNIT

OFF Figure 17:

Lower bankof Middle bankof DIP switches DIP switches

2

(199X3P) 1

fi PARENT ed modelinanEasy-Link System asshowninTable 6:onpage 35.Oneheater (540) or on. Refer to theEasy-Link System sec

DIP switch location ons withPrevious Models

1 2 3 4 5 6 2 CHILD UNIT ON Lower Bank Middle Bank Upper Bank

OFF

Middle bankof

Lower bankof

DIP switches DIP switches 1

(199X3P) 2 PARENT (540) or on intheheater’s installa Connectors

1 2 3 4 5 6 3 CHILD UNIT ON

OFF

fi Middle bankof

Lower bankof gures 17&18.The CHILDunits

DIP switches DIP switches 2

(199X3P) 1 PARENT (540) or fl owrate. Thewater on manualfor SERVICE PROCEDURES 0 On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 35 540H540H540H 540H 540H 540H 540H 540H 540H 199X3P199X3P 540H 199X3P 540H 540H 199X3P 199X3P199X3P199X3P199X3P 199X3P 199X3P 540H 540H 540H 540H n/a 540P 540H 540H 540H 199X3P 199X3P 199X3P 199X3P 199X3P unit will display “000” for 10 seconds to signify that the computer memory of the previously assigned unit # has been memory of the previously the computer signify that to 10 seconds “000” for unit will display erased. will be assigned in this order. The new unit numbers Parent UnitParent Combinations) Child Unit (Unacceptable Parent UnitParent Combinations) (Acceptable Child Unit 1. turns off. LED unit so the Standby of the parent on the controller Push the ON/OFF button 2. 5 seconds. least at unit for on the PCB of the Parent button and hold the “Increase” Press 3. of the Child the same time the controller At 10 seconds. unit will blink for LED on the PCB of the Parent The green 4. choice. of your unit in the new order on each Child button the “Increase” and release period press During the 10 second • The Parent unit is assigned automatically No. 1 in the system and the number isn’t displayed on the controller. on and the number isn’t displayed No. 1 in the system unit is assigned automatically • The Parent 4. assigned 2 to randomly • Child units are and act will be ignored wire via the Easy-Link additional units connected only link 4 units. Any can • The system System. of the Easy-Link independently Unit #’s can be reset and reassigned manually: and reassigned be reset can Unit #’s B. How to reset and reconfigure the numbering of units and reconfigure reset B. How to NOTE: second. The number can also be accessed through the Diagnostic Mode under Information Mode 32. See Table 7 on page 39. 7 on page See Table Mode 32. under Information Mode the Diagnostic through also be accessed The number can second. Press the “Increase” button on the PCB of a Child unit. The controller of the Child unit will display the assigned number for 1 the assigned number for of the Child unit will display on the PCB of a Child unit. The controller button the “Increase” Press Easy-Link Unit Number Display and Renumbering Procedure (for 199X3P Models Only) (for Procedure Unit Number Display and Renumbering Easy-Link the unit number display A. How to Table 6: Table SERVICE PROCEDURES Figure 19: automatically after 30minutes. NOTE: You may exit diagnostic modebypressing theON/OFFbutton. Also, ifleft alone,thedisplay willexit diagnostic mode 36 • On-Demand Water Heater Handbookfor Service X3PModels through anEasy-Link system. even ifthey are linked together about oneormore water heaters, discover various piecesofinformation Diagnostic modeallows you to Diagnos o Descrip No. 4 3 2 1 NOTICE

Built-in andRemote controller settings. "ON/OFF" "INFO." "COLD" Bu Bu Bu Bu "HOT" ƩŽŶ ƩŽŶ ƩŽŶ ƩŽŶ ƟŽŶ • • Thebackli • c Mode ƚŚĞďĂĐŬůŝŐ dŚĞĐŽŶƚƌŽůůĞƌŚĂƐĂŶĞŶĞƌŐLJƐĂǀŝŶŐŵŽĚĞ͘&ŝǀĞŵŝŶƵƚĞƐĂŌĞƌƚŚ tŚĞŶƚŚĞƌĞŵŽƚĞĐŽŶƚƌŽůůĞƌŝƐŝŶƐƚĂůůĞĚŝƚǁŝůůƚĂŬĞƉƌŝŽƌŝƚLJŽ -Inlet/Outlet Water Temperature -Pump Status/Se -Water FlowRate Press the"INFO" bu bu Press the"HOT" bu Press thisbu perature, thecurrent opera TIMER Ʃ on to settheoutletwater tem- 4 Built-in controller ƟŽŶ͘ Ő ͘ ht oftheremote willturnbackononcethewater heater b ht ofthecontroller turnso 5 Ʃ on to start orstop ƫŶŐƐ oeN.Descrip No. Note 67 Ʃ Ʃ on orthe"COLD" . UsetheHOT orCOLD buttons to scroll 2. To enter diagnostic mode, press the 1. Individual Unit on to display: ƟŵĞ͕ number. until you reach thedesired mode through themodenumbers. Continue seconds. Figure 19. simultaneously for at least five HOT button andtheCOLD button meanings. for alist ofmodenumbers andtheir andPUMP

See Table 7onpage 38. 1 3 9 2 8 ī͘ 9 8 7 6 5 STAND BY LED Remote controller IN USELED "PUMP" 5 "TIME" Bu Bu LCD ƩŽŶ ƩŽŶ 71 47 ƟŽŶ 68 ǀĞƌƚŚĞďƵŝůƚͲŝŶĐŽŶƚƌŽůůĞƌ͘ ĚŝƐƉůĂLJĞĚ͘ error codeandother ƟŵĞ͘ The LED The LED Press thisbu The current Press this pump opera ĞǁĂƚĞƌŚĞĂƚĞƌƐƚŽƉƐŽƉĞƌĂƟŶŐ . To exit diagnostic mode,press and 4. Press theINFO button to selectthe 3. ĞŐŝŶƐĮ seconds. simultaneously for at least five hold theHOT andCOLD buttons display onthecontroller. mode number. Theinformation will ůŝŐ ůŝŐ ďƵƩŽ hts when power is is power when hts hts rin ƟŽŶ͘ ƟŵĞ͕ Ʃ 9 3 2 on to setandcontrol the ĚƵƌŝŶŐ Ő n tosetthecurrent a Note settemperature, Ő ain combus ŝŶĨŽƌŵĂƟ ͘ ƟŽŶ͘ ŽŶ͘ on are , SERVICE PROCEDURES ld simultaneously for at least five seconds. five least at for simultaneously ŽƌŵĂƟŽŶ NOTE: You may exit diagnostic mode by mode by diagnostic exit may You NOTE: if Also, button. the ON/OFF pressing diagnostic will exit display alone, the left 30 minutes. after mode automatically Inf Mode no. See Table 7, page 38 for a list 38 for 7, page See Table be linked can that ons On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 37 of mode numbers and their meanings. of mode numbers will be The data the mode number. (Figure on the controller. displayed water the outlet that 21 shows is 120 of this heater temperature degrees.) buttons and COLD hold the HOT together in an Easy-Link System. System. in an Easy-Link together unit number. desired or COLD the HOT press selected, the desired to scroll to button (mode number). Figure information number 6 is mode that 20 shows selected. that are installed in the Easy-Link in the Easy-Link installed are that allowable 6 for See Table system. combina 6. 6. select to button the INFO Press 7. and mode, press diagnostic exit To 4. 4. select the to button the INFO Press 5. unit number is When the desired on Unit no. on about the up or scroll on to mode e l o ƟĐ Multiple unit temperature display. temperature Multiple unit

Wh System a Linked ple Units in unit will not display the set temperature. the set unit will not display NOTE: “0” will yield information “0” will yield information NOTE: as a whole. system about the linked “1” will yield informa down. (Figure 20 shows that unit no. that 20 shows down. (Figure 2 is selected.) system. unit in a Easy-Link parent & ”4” will yield informa “3”, “2”, heaters about each of the water Figure 20.) Figure the by pressing system the linked bu or COLD HOT Press the HOT button and the COLD and the COLD button the HOT Press least at for simultaneously button 19. See Figure seconds. five this step on the parent heater or on or on heater on the parent this step the to is attached that the remote unit: parent

diagnos • number 1. be heater will always heater the parent system, In an Easy-Link • of the chi controller the System, in an Easy-Link temperature the set unit will display of the parent Although the controller NOTE: Figure 20: Figure • system. 2 in a linked unit for temperature the outlet displaying for the steps shows This example This example shows the steps for displaying the outlet temperature for unit 2 in a linked system. unit 2 in a linked for temperature the outlet displaying for the steps shows This example 2. 2. (See on the controller. “0” will display 3. number in unit the desired to Scroll Mul 1. mode, complete diagnostic enter To SERVICE PROCEDURES 38 • On-Demand Water Heater Handbookfor Service X3PModels Diagnostic Modes Table 7: Press the“ * clear thememory oe#Whole Easy-Link System informa # Mode EEPROM 12 11 10 18 14 13 17 16 15 9 3 Total system 1 2 4 5 e eprtr 0 o10° Outlettemperature 100to 140°F Set temperature 6 8 7 /ŶŝƟĂůŝ INFO Qua the BTU requireme /Ŷů ƵŶŝƚŶƵŵďĞƌ Priority water heater heaters water Outlet temperature of the priority Qua the priority heaters opera curre ON/OFF cycles Opera curre et temperature of ” DƵůƟͲ ŶƟƚLJ ŶƟƚLJ za ďƵƩŽŶ Ŷ Ŷ ƟŽŶĂů ŝŶ ƟŽŶ t rota t rota ƟŽŶ theerror code history. ofc of System

ofwater heater's computer ƟŵĞ

water ŽŶ ƵŶŝƚ ƵŶŝƚ ƟŽŶ ƟŽŶ Ň ŽŶŶĞĐ theco wrt o99(P)Total opera 0to 999(GPM) ow rate Ŷ ĚƵƌŝŶŐ

ĚƵƌŝŶŐ t for ted ted Ŷ N/A N/A troller while rota o99 ×BUh ON/OFF cycles 0 to 999(×kBTU/h) A 0 to 100(cycles) hŶĚĞƌ 199X3P: 1to4 160/180X3P: 1to2 199X3P: 1to4 160/180X3P: 1to2 Over 212°F=E5, 32 to 212(°F) 199X3P: 1to4 160/180X3P: 1to2 rota A 0 to 720 Ō Ō er 100,the er 720,the ƟŽŶ ƟŽŶ 32°F=E0 occurs occurs ;ŵŝŶ ŝŶ mode#14 Ɵ : on (#0) Unit informa Unit on (#0) utes) Ŷ Ŷ ext ext ext ext ĂŶĚ lwrt 0to 999(×0.1GPM) Flow rate dŝŵĞƵŶŝƚŚĂƐWŽǁĞƌ Error code history: displays the error code Error code history: displays themost rece through theheater dŽƚĂůǁĂƚĞƌŇŽǁ /Ŷů F rece rece Clears thememory Exhaust temperature of theheater dŽƚĂůĞŶĞƌŐLJŽƵƚƉƵƚ Error code history: displays the3rd most temperature Heat ex Flame r value Curre ĂŶ mode#25for at least 3sec et temperature motor speed 0 to 0 999(×10rpm) motor speed Ŷ Ŷ Ŷ t error code t error code t airpressure ŽĚĐƵƌƌĞŶƚ ĐŚĂŶ N/A ƟŽŶ ger ger

ƟŵĞ ŝŶ error code history* ƟŽŶ (× 1,000cycles) 0 to 999 0 to 999(x100hours) 0 to 999(×100hours) hŶĚĞƌ (× 10,000g 0 to 999 hŶĚĞƌ Over 212°F=E5, 32 to 212(°F) Over 212°F=E5, 32 to 212(°F) 0 to 999MBTU/h 0 to 999 (#1to #4) ŽŶĚƐ 32°F=E0 32°F=E0 (x 10mV) to completely completely to N/A ϮŶĚ ;ʅͿ ĂůůŽŶƐͿ most Ŷ t SERVICE PROCEDURES = 10 stage ďƵƌŶŝŶŐ = 164 ompletely ompletely ηϰͿ ϮŶĚ Đ 3rd stage 3rd 4th stage No

1st stage 1st ŽƉĞŶ to ƉŽƐŝƟŽŶ to 32 °F = E0 Full ŵĞĂŶƐ ŵĞĂŶƐ ŵĞĂŶƐ ŵĞĂŶƐ ŵĞĂŶƐ ;ηϭ

ĐŽŶĚƐ 0 to 999 (x 10,000 ŐĂůůŽŶƐͿ 160/180X3P: 1 to 2 199X3P: 1 to 4 0 to 999 (%) 0 to 0 to 999 (x 10 steps) 999 0 to Closed “3” “4” “0” 32 to 212 (°F) 32 to °F = E5, 212 Over hŶĚĞƌ 0 to 999 (kBTU/h) 0 to “2” 0 to 999 (kBTU/h) 999 0 to 0 to 999 (x 100 hours) 0 to 0 to 283 (steps) “1” ƟŽŶ ) ) ŝŶ ŝŶ ƟŽŶ -T ƟŵĞ -T

za set out ƉŽƐŝƟŽŶ or at least 3 se least or at ƟŽŶ Ĩ /ŶŝƟĂůŝ Unit informa temperature ƚƵƌŶ mode# 25 dŽƚĂůŇŽǁƚŚƌŽƵŐŚyϯ hŶŝƚEƵŵďĞƌŝŶ ĂƐLJͲ>ŝŶŬ Flow rate through Flow rate through bypass valve Bypass valve ƐƟŵĂƚĞĚŽƵƚƉƵƚ 500 x GPM x (T ĐƚƵĂůŽƵƚƉƵƚ 500 x GPM x (T EEPROM EEPROM ZĞƐĞƚyϯŇŽǁǀŽůƵŵĞ;ŵŽĚĞϯϭͿΎ WŽƐŝƟŽŶŽĨŝŶůĞƚĂŝƌ damper ƵƌƌĞŶƚĐŽŵďƵƐƟŽŶ ƐƚĂŐĞŝŶŽƉĞƌĂƟŽŶ ĂŶĚ : mode# 14 ŝŶ On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 39 troller while troller N/A Ŷ o Đ ode history. Đ the ŽŶ

of water heater's computer heater's of water ƩŽŶ the error the error ƟŽŶ ŝŶ za ” bu tŚŽůĞĂƐLJͲ>ŝŶŬ^LJƐƚĞŵŝŶĨŽƌŵĂƟŽŶ;ηϬͿ INFO /ŶŝƟĂůŝ 28 N/A 20 21 Re 29 22 Pump speed 999 (× 10 rpm) 0 to 30 19 31 32 2324 Pump opera N/A N/A 25 26 27 the memory Mode # EEPROM EEPROM ĐůĞĂƌ Press the “ Press Ύ SERVICE PROCEDURES 40 • On-Demand Water Heater Handbookfor Service X3PModels Figure 21: MAINTENANCE 24

System component locations 20 22 23 21 20 25 27 29 30 31 26 28 32 33 34 53 37 36 35 19 17 14 38 42 18 39 16 40 15 10 13 12 4 8 6 9 3 1 7 11 5 2 41 MAINTENANCE

ŝŶ 3 4 2 0 7 3 2 2 2 2 6 3 9 4 2 8 1 0 8 8 9 9 5 4 9 7 1 1 4 0 0 2 3 0 1 1 2 0 0 0 0 0 0 1 8 3 0 0 0 2 0 0 1 1 1 0 0 3 0 4 1 718 434 4 1 0 103 4 112 4 109 411 7 1 1 7 7 0 7 1 1 4 7 4 1 4 7 4 4 4 731 4 726 407 0 4 123 7 4 469 (118) diagram Item # ĐŽŵƉŽŶĞŶƚƐ port) assembly assembly fuse ǀĞŶƟŶŐ tray pump Žī ƉůƵŐ

thermistor rod

box assembly ĂƌƚƌŝĚŐĞ ĞdžĐŚĂŶŐĞƌ ĮůƚĞƌ ĞdžĐŚĂŶŐĞƌ 1 Gas inlet ^ƵƌŐĞ ƉƌŽƚĞĐƟŽŶ Drain port Fan motor /ŐŶŝƚĞƌ Water inlet Inlet heater chamber assembly Air inlet tube Bypass valve Exhaust duct 120 VAC wire X3™ ĞƐĐƌŝƉƟŽŶ Hi-limit switch Case assembly Inlet Flame Sensor Main Gas Valve Pressure sensor Inlet thermistor ĞdžĐŚĂŶŐĞƌ /ŐŶŝƚĞƌ

Computer board Built-in controller Return thermistor Return water inlet Exhaust thermistor Gas valve assembly ZĞĐŝƌĐƵůĂƟŽŶ Rain Air damper assembly Overheat-cut- Condensate drain port X3™ manifold assembly VAC Power ON-OFF switch Water outlet (with PRV) Gas inlet port (Gas inlet) DŝdžŝŶŐ Heat Gas solenoid valve assembly On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 41 120 Primary heat Flow adjustment valve/Flow sensor Secondary heat Exhaust port cap (Outlet 9. 5. 6. 7. 8. 4. 1. 2. 3. 39. 40. 41. 42. 38. 36. 37. 34. 35. 32. 33. 31. 30. 29. 25. 26. 27. 28. 10. 11. 13. 14. 15. 16. 24. 17. 18. 19. 20. 21. 22. 12. 23. Table 8: Table VIEW IN THE INTERIOR OF MAIN COMPONENT LIST No. MAINTENANCE 42 • On-Demand Water Heater Handbookfor Service X3PModels shuto The power bu at thecircuit breaker, asappropriate. Exhaust Port Cap: Removing andreplacing the OVER TIGHTENING. TIGHTEN ALLSCREWSTO PREVENT SCREWDRIVERS ORDRILLS,HAND NOTICE: DONOT USEELECTRIC #2 PhillipsScrew Driver Tools: • Ifyou donothave theskills • To ensure your safety andthe Exhaust Port Cap Replacing the Removing and working onor near any electrical parts. confirm that power isoff before Use anon-contact circuit tester to water heater. physically disconnect power to the power to thewater heater. You must and remote does NOT disconnect 3 2 1 personal injuryordeath. Failure to dosocouldresult in each step oftheseinstructions. safety ofothers, read andfollow technician. assistance from aqualifiedservice correctly, donot proceed. Seek necessary complete thisprocedure WARNING ff valve. Use aPhillips-headscrewdriver to Shut o Disconnect power to thewater water heater at the manualgas remove the4screws securingthe the wall outlet orturningitoff heater itfrom byunplugging ff thegas supplyto the on thewater heater

for re-installa Set thefront cover andscrews aside cover to thewater heater. SeeFigure 22. Figure 23: Figure 22: Use a the plas remove andkeep thescrew securing heater. Inspectthegasket on thenew exhaust port. 4 5 FRONT COVERSCREWS Phillips-head Carefully pulltheoldplas Reference Figure 23for the loca exhaust portcap from thewater

Front cover removal. Exhaust portcap removal. c exhaust portcap to the on oftheexhaust portcap. on. screwdriver to screwdriver to c • To ensure your safety andthe Assembly Replacing theFan and Removing alignment. alignment. front cover inplaceto ensure proper the builtincontroller whense removed earlier. Note theplacement of cap to ensure that itisproperly seated. Figure 23.Checkthenewexhaust port it withthescrew removed earlier. See heater backon. the On/O circuit breaker, asappropriate. Press wall outlet orturningitonat the shuto poisoning ordeath. follow can cause carbon monoxide exhaust gases from leaking.Failure to must beproperly seated to prevent condi exhaust portcap, ensure that itisgood 11 10 8 7 9 personal injury ordeath. Failure to dosocouldresult in each step oftheseinstructions. safety of others, read andfollow WARNING! Theexhaust portcap WARNING ff on. on. valve. Replace thefront cover and Place thenewexhaust portcap Verify proper opera Reconnect power to thewater Turn onthegas supplyto the secure withthefour screws on theexhaust vent andsecure water heater. heater itinto byplugging the water heater at themanualgas ff bu on to turnthewater on of the on ofthe ng the MAINTENANCE the two R,W,BK Pressure Sensor Connector Fan Assembly Fan Venturi Body Venturi on. Remove Remove on. Y,O,W,R,BR Connector Air Damper 16-25A Fastener Fan Motor Assembly Wire Connections Assembly Wire Motor Fan

Remove screws securing the fan as- fan securing the screws Remove Gas Pipe and Fan Motor Assembly Motor Gas Pipe and Fan

Copper Gas Pipe assembly from the water heater. the water assembly from the fan body to the venturi fasteners on both ends of the on both ends of fasteners Remove the complete Fan Motor Fan the complete Remove securing screws the four Remove Remove the 16-25A metal the 16-25A metal Remove R,LB,G,B Gas Solenoid 11 12 10 Valve Connector Valve screws securing the fan motor to the to motor securing the fan screws mixing chamber assembly. assembly. See Figure 27. See Figure assembly. 27: Figure sembly. copper gas pipe (#104) and set them set pipe (#104) and gas copper re-installa aside for 26: Figure removal. Figure 25: Figure fy om ons. ables c housing c c computer c housing out from the water the water c housing out from Computer Board Bracket. Board Computer

controller and follow it to the it to and follow controller Locate the wire on the built in the wire Locate on. Slide the computer board board the computer on. Slide on. board housing on the bo housing board on the fan motor assembly to their assembly to motor on the fan from the computer board. the computer from Locate and follow the three c the three and follow Locate Disconnect the fan motor cable motor the fan Disconnect Locate the plas the Locate c housing for the computer board. board. the computer c housing for c connectors. Disconnect and move Disconnect c connectors. On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 43 7 9 8 6 cables. and plas Keep the screw and bracket for re- for and bracket the screw Keep installa connec access the cable to heater 24. See Figure them aside. Reference Figure 25 to iden 25 to Figure them aside. Reference back into the water heater to prevent prevent to heater the water back into on the cables. unnecessary tension right side of the water heater. Remove Remove heater. side of the water right securing the bracket and the screw plas computer board. Carefully disconnect Carefully board. computer the computer from the built in controller on the wiring diagram Reference board. sheet. 28 or in the maintenance page re- aside for controller the built-in Set installa plas Reference the wiring diagram on page wiring diagram the Reference Slide sheet. 28 or in the maintenance and plas board the computer Figure 24: Figure on on. c cable on. on plate from the water the water from on plate the gas supply to the supply to gas the ff side of the rain protec side of the rain clips securing the various cables clips securing the various Remove the white plas the white Remove on tray for re-installa for on tray le remove the 4 screws securing the the 4 screws remove heater by unplugging it from by unplugging it from heater or turning it off outlet the wall water heater at the manual gas the manual gas at heater water Remove the screw securing the the screw Remove Shut o to Use a Phillips-head screwdriver Disconnect power to the water the water to power Disconnect valve. ff necessary complete this procedure this procedure complete necessary Seek proceed. do not correctly, a qualified service from assistance technician. 5 4 3 2 1 heater. Keep the screws with the rain rain with the the screws Keep heater. protec to the copper gas pipe. gas the copper to tray. Remove and keep the front right the front and keep Remove tray. Slide port assembly. in the intake screw protec the rain cover to the water heater. Set the front the front Set heater. the water to cover re-installa aside for and screws cover Use a non-contact circuit tester to to tester circuit Use a non-contact before is off power that confirm parts. electrical on or near any working at the circuit breaker, as appropriate. breaker, the circuit at heater water on the button The power disconnect does NOT and remote must You heater. the water to power the to power disconnect physically heater. water Removing the Fan Assembly the Fan Removing Tools: (8” or Head Screwdriver #2 Phillip’s tip), Pliers. with magnetic longer USE ELECTRIC DO NOT NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TO TIGHTEN ALL SCREWS TIGHTENING. OVER • If you do not have the skills the skills do not have • If you shuto MAINTENANCE kit. SeeFigure 28. the o-ringswithonesprovided inthe poisoning ordeath. follow can cause carbon monoxide exhaust gases from leaking. Failure to be properly installed to prevent 44 • On-Demand Water Heater Handbookfor Service X3PModels assembly, asshowninFigure 28. Figure 28. venturi body asshowninSeeFigure 28. body, theninserttheventuri ductinto the Replacing thefan assembly: plas assembly. Figure 28: See Figure 28. body andset asidefor re-installa 17 16 15 14 13 WARNING! Thefan assemblymust c venturi ductfrom theventuri Make sure o-ringP75(#134)is Insert theventuri ductinto the Make sure o-ringP50(#132)is Before a Separate thefan assemblyfrom to thenewfan assembly, replace seated properly inthenewfan venturi bodyasshowninSee seated properly in theventuri the venturi body. Remove the

Removing thescrews securingthefan Fan Assembly aching theventuri body O-Ring P75,#134 Venturi Duct Venturi on. on. immediately. SeeFigure 28. nicks are present replace them pipe. Inspecttheo-rings,ifany cutsor fasteners onbothendsofcopper gas the wiringdiagram on page 28.Once to iden plas earlier. Secure itwiththetwo screws removed connec new fan assembly. Itisessen orienta Reference Figure 28for correct with thefour screws removed earlier. correct them immediately. leaks. Checkthisunionfor any issues, the venturi bodynothave any gaps or O-Ring P50,#132 22 21 20 19 18 c connectors. Reference Figure 25 Reconnect thefan motor cable to Reconnect thethree cables on Reconnect thecopper gas pipe(# Rea Rea the computer board. Refer the fan motor assemblyto their 104). A mixing chamberassembly(#112). new fan assemblyandsecure on oftheventuri bodyto the fy cables. onbetween thefan motor and ach thefan assemblyto the ach theventuri bodyto the Venturi Body ach the16-25Ametal al that the al that the ence ence maintenance sheet for diagram onpage 28orinthe computer board. Refer the wire from thebuiltincontroller to the and plas connected, slidethecomputer board alignment. alignment. front cover inplaceto ensure proper the builtincontroller whense removed earlier. Note theplacement of fasteners removed earlier. SeeFigure 26. immediately. Usethe16-25Ametal nicks are present replace them tee. Inspecttheo-rings,ifany cutsor exchanger outlet and thewater outlet assembly. the front right screw intheintake port Figure 24. bracket andscrew removed earlier. See water heater. Secure itinplacewiththe series ofver series ofver heater. removed earlier. Re-a correctly andseated securely. pipe connec side ofthewater heater. side ofthewater heater. 25 24 23 30 30 29 28 27 26 Re-install therain protec Slide theplas A Replace thefront cover and Before proceeding ,take amoment Use thewhite plas Reconnect thecopper pipe(# Usethewhite plas front ofthewater heater. Reconnect computer board backinto the secure withthefour screws to checkallwiringconnec 468) to the primary heat removed earlierto organize the removed earlierto organize the and secure itwiththescrew ach thebuiltincontroller to the c housingbackinto thewater ons. Make sure allare mated cal cables alongtheright cal cables alongtheright c housing with the c housingwiththe plug loca ach and ach ence the wiring ence thewiring c cable clips c cable clips clips cable c on. on. ons and ng the the ng on tray ghten MAINTENANCE on. or plug ons and ons sheet f Figure 29 Figure for See Figure 29. See Figure e mated all are sure ons. Make Pip ss ach the built-in controller to controller ach the built-in Copper gas pipe removal Copper gas

gas pipe from the water heater. heater. the water pipe from gas Carefully remove the old copper remove Carefully >ŽǁĞƌŽŶŶĞĐƟŽŶ to check all wiring connec to Inspect the o-rings, if any cuts or Inspect the o-rings, if any on both ends of the fasteners the front of the water heater. heater. of the water the front Before proceeding , take a moment , take proceeding Before Install the new copper gas piping. gas the new copper Install the 16-25A metal Re-install A hƉƉĞƌŽŶŶĞĐƟŽŶ on. WARNING! The copper gas pipe copper gas The WARNING! 6 Copper Gas PipeCopper Ga 7 8 9 10 correctly and seated securely. and seated correctly pipe connec See Figure 30. See Figure must be properly installed to prevent prevent to installed be properly must to leaking. Failure from gases exhaust monoxide carbon cause can follow poisoning or death. them replace present are nicks Reference immediately. pipe (# 104). gas copper Figure 30: Figure pipe: the copper gas Replacing and orienta part placement correct Reconnect the wire from the built-in the built-in from the wire Reconnect board. the computer to controller on page the wiring diagram Reference 28 or in the maintenance loca on. ste Fa tal Me 25A2 16-25A Metal Fastener 16-25A Metal 16- on. 29. See Figure the gas supply to the supply to the gas ff e 16-25A Metal Fastener 16-25A Metal p ipe hƉƉĞƌŽŶŶĞĐƟŽŶ >ŽǁĞƌŽŶŶĞĐƟŽŶ PPi fasteners on both ends of the on fasteners Remove the 16-25A metal metal the 16-25A Remove Gas pipe connection.

controller and follow it to the it to and follow controller Locate the wire on the built-in on the built-in the wire Locate on. remove the 4 screws securing the the 4 screws remove water heater at the manual gas the manual gas at heater water Shut o to Use a Phillips-head screwdriver valve. ff per Gas P 5 On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 45 4 2 3 Copper Gas PipeCopper Gas P Copper Gas PipeCop copper gas pipe (# 104) and set them pipe (# 104) and set gas copper re-installa aside for computer board. Carefully disconnect Carefully board. computer the computer from controller the built-in on the wiring diagram Reference board. sheet. 28 or in the maintenance page re- aside for controller the built-in Set installa cover to the water heater. Set the front front the Set heater. the water to cover re-installa aside for and screws cover Figure 29: Figure Use a non-contact circuit tester to to tester circuit Use a non-contact before is off power that confirm parts. electrical near any on or working shuto

ff on of the

heater by unplugging it from by unplugging it from heater or turning it off outlet the wall water heater at the manual gas the manual gas at heater water the wall by plugging it into heater heater. water Disconnect power to the water the water to power Disconnect Verify proper opera proper Verify Turn on the gas supply to theto supply on the gas Turn Reconnect power to the water the water to power Reconnect valve. ff

back on. heater turn the water on to WARNING! WARNING! necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. safety of others, read and follow and follow read of others, safety these instructions. of each step in do so could result to Failure injury or death. personal 1 33 32 31 at the circuit breaker, as appropriate. breaker, the circuit at heater on the water button The power disconnect does NOT and remote must You heater. the water to power the to power disconnect physically heater. water bu Copper Gas Pipe Replacing the Replacing Removing and Removing shuto the circuit at or turning it on outlet the On/O Press as appropriate. breaker, • To ensure your safety and the safety your ensure • To the skills do not have • If you pipe: the copper gas Removing Head Needed: #2 Phillip’s Tools Screwdriver. USE ELECTRIC DO NOT NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TIGHTEN ALL SCREWS TO TIGHTENING. OVER MAINTENANCE appropriate connec leaks are detected, re-seat the OVER TIGHTENING. TIGHTEN ALLSCREWSTO PREVENT SCREWDRIVERS ORDRILLS,HAND NOTICE: DONOT USEELECTRIC Screwdriver. Tools Needed:#2Phillip’s Head Removing theventuri assembly: • Ifyou donothave theskills • To ensure your safety andthe on. 46 • On-Demand Water Heater Handbookfor Service X3PModels Venturi Assembly Replacing the Removing and O breaker, asappropria wall outlet orturningitonat thecircuit alignment. front cover inplaceto ensure proper the built-in controller whense removed earlier. Note theplacement of shuto 14 13 12 11 ff personal injuryordeath. Failure to dosocouldresult in each step oftheseinstructions. safety ofothers, read andfollow bu qualified service technician.qualified service proceed. Seekassistance from a procedure correctly, donot necessary to complete this WARNING! ff valve andcheckfor leaks. Ifany Verify proper opera Reconnect power to thewater Replace thefront cover and Turn onthegas supplyto the water heater. heater itinto byplugging the secure withthefour screws water heater at themanualgas on to turnthewater heater back on(s) andre-check. te. Pr ess theOn/ on ofthe ng the the ng shuto working onornearany electrical parts. confirm that power isoff before Use anon-contact circuit tester to Figure 31: plas cover andscrews asidefor re-installa cover to thewater heater. Set thefront water heater. physically disconnect power to the power to thewater heater. You must and remote does NOT disconnect The power button onthewater heater at thecircuit breaker, asappropriate. to thecopper gas pipe. 3 2 1 5 4 c connectors. Disconnect andmove ff valve. Locate andfollow thethree cables on Use aPhillips-headscrewdriver to Shut o Disconnect power to thewater water heater at themanualgas the fan motor assembly to their the fan motor assemblyto their remove the4screws securingthe the wall outlet orturningitoff heater itfrom byunplugging Remove thewhite plas clips securingthevarious cables

Fn Assembly Fan ff the gas supplyto the Fan Assembly O-Ring P75,#134 Venturi Duct Venturi c cable cable c O-Ring P50,#132 on. Gas SolenoidAssembly Venturi Assembly, #126 Figure 33: aside for re-installa copper gas pipe(#104)andset them Figure 32: them aside.Reference Figure 33to iden mixing chamberassembly. SeeFigure 34. screws securingthefan motor to the cables. Valve Connector 6 Gas Solenoid R,LB,G,B Remove the16-25Ametal fasteners onbothendsofthe

GasPiperemoval.

Fan Motor AssemblyWire Connections Copper GasPipe O-Ring P40,#125 Air Damper 16-25A Fastener Connector Y,O,W,R,BR on. Remove Air DamperAssembly Connector Sensor Pressure R,W,BK the two the two fy fy MAINTENANCE on of the ess the On/ te. Pr te.

ce Assembly ce back heater turn the water on to heater by unplugging it from by unplugging it from heater or turning it off outlet the wall heater by plugging it into the the by plugging it into heater heater. water Disconnect power to the water the water to power Disconnect Reconnect power to the water the water to power Reconnect opera proper Verify fi WARNING! WARNING! necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. bu safety of others, read and follow and follow read of others, safety these instructions. of each step in do so could result to Failure injury or death. personal ff 1 22 23 at the circuit breaker, as appropriate. as appropriate. breaker, the circuit at heater on the water button The power disconnect does NOT and remote must You heater. the water to power the to power disconnect physically heater. water wall outlet or turning it on at the circuit the circuit at or turning it on outlet wall as appropria breaker, and the safety your ensure • To the skills do not have • If you orifice assembly: gas the Removing Head Needed: #2 Phillip’s Tools Head #2 Phillip’s Screwdriver, with magnetic (8” or longer Screwdriver tip) USE ELECTRIC DO NOT NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TIGHTEN ALL SCREWS TO TIGHTENING. OVER O on. Removing, and Replacing, the Gas Verifying Ori on(s) ng the ons and ons Figure 32Figure on. c cable clipsc cable ach the 16-25A metal ach the 16-25A metal cal cables along the right along cables cal on. on. mated all are sure ons. Make the body to venturi ach the fy cables. fy secure with the four screws screws with the four secure removed earlier to organize the organize earlier to removed check all wiring connec to the manual gas at heater water 104). A their assembly to motor the fan fan assembly. Inspect the O-ring, assembly. fan assembly and secure new fan Replace the front cover and cover the front Replace Use the white plas Use the white a moment , take proceeding Before the supply to on the gas Turn Reconnect the copper gas pipe (# gas the copper Reconnect on cables the three Reconnect Install the new P75 O-ring on the Install Rea supply on and the gas Turn valve. ff c connectors. Reference Reference c connectors. On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 47 21 18 19 20 16 17 14 15 ghten the appropriate connec the appropriate ghten side of the water heater. side of the water pipe connec securely. and seated correctly to iden to front cover in place to ensure proper proper ensure in place to cover front alignment. removed earlier. Note the placement of the placement Note earlier. removed when se controller the built-in series of ver shuto and re-check. plas if any cuts or nicks are present replace it replace present are cuts or nicks if any 31 See Figure Reference immediately. part placement correct 46. for on page and orienta earlier. removed screws with the four correct 46. for 31 on page See Figure and orienta part placement immediately. Reference See Figure 31 See Figure Reference immediately. part placement correct 46. for on page and orienta check for leaks. If any leaks are detected, detected, are leaks If any leaks. check for fasteners on both ends of copper gas gas both ends of copper on fasteners cuts or pipe. Inspect the O-rings, if any them replace present are nicks immediately. on. Keep the on. Keep on. on. O-ring P50 into the new venturi the new venturi O-ring P50 into from the gas valve solenoid valve the gas from new venturi assembly and secure assembly and secure new venturi screws securing the air damper screws screws securing the gas valve valve securing the gas screws securing the venturi body to fan fan body to venturi securing the duct, and P50O-ring, venturi Insert the new venturi duct and Insert the new venturi Place the O-ring removed earlier Place the O-ring removed Place the new P40 O-ring on the Remove and set aside the three aside the three and set Remove Remove and set aside the three aside the three and set Remove Unscrew and keep the 4 screws the 4 screws and keep Unscrew aside the old P75 and set Remove WARNING! The venturi assembly The venturi WARNING! 9 8 7 13 12 11 10 gasket safe from damage. from safe gasket assembly. Inspect the O-ring, if any cuts Inspect the O-ring, if any assembly. it replace present are or nicks assembly on the new venturi assembly. assembly. assembly on the new venturi cuts or nicks Inspect the O-ring, if any it immediately. replace present are the new solenoid to valve the gas Secure screws assembly with the three venturi See Figure Reference earlier. removed part correct 46. for 31 on page and orienta placement the air damper assembly to the new the air damper assembly to Inspect the O-ring, if assembly. venturi it replace present are nicks cuts or any 31 See Figure Reference immediately. part placement correct 46. for on page and orienta assembly to the venturi assembly. Set assembly. the venturi assembly to 31 aside the old P40 O-ring. See Figure 46. on page assembly: the venturi Replacing solenoid assembly to the venturi the venturi to solenoid assembly aside the assembly and Set assembly. re-installa for gasket assembly. See Figure 31 on page 46. on page 31 See Figure assembly. 46. 31 on page O-ring. See Figure must be properly installed to prevent prevent to installed be properly must to leaking. Failure from gases exhaust monoxide carbon cause can follow poisoning or death. MAINTENANCE proceeding. system to completely drain before and openthedrain port.Allow the Place abucket underthewater heater 48 • On-Demand Water Heater Handbookfor Service X3PModels Replacing thegas orificeassembly: Figure 35. the various wiringconnec This can bedonewithoutdisconnec 35. valve assemblyto thefan assembly. removal. Figure 34: aside for re-installa copper gas pipe(#104)andset them shuto working onornearany electrical parts. confirm that power isoff before Use anon-contact circuit tester to installa assembly. Set thescrews aside for re- ori Figure 35. 3 2 5 4 8 7 6 fi ce gasket to thegas solenoidvalve ff valve. Separate thegas solenoidvalve Remove theoval O-ring Remove andset asidethe two Remove andset asidethethree Remove the16-25Ametal Shut o Shut o heater anddrain thesystem. screws securing theori assembly from thefan assembly. screws securingthegas solenoid fasteners onbothendsofthe water heater at themanualgas the gas solenoidvalve assembly. See on. See

GasPipeandFan Motor Assembly Copper GasPipe ff ff thegas supplyto the 16-25A Fastener water to thewater Figure 35. on. See Figure 34. ons. See See ons. fi ce and and ce 1 Figure from from ng ng See with thetwo screws removed earlier. oriented. Secure theori All holeswilllineupifitiscorrectly Note theorienta poisoning ordeath. follow can cause carbon monoxide exhaust gases from leaking.Failure to must beproperly installed to prevent ori See Figure 35for assemblyorder andgas new oval O-ring screws removed earlier. Make sure the assembly. Secure itwiththethree ori of gas you are using. placement. 28 orinthemaintenance sheet for Reference thewiringdiagram onpage not pinched. 3 2 10 1 9 11 fi fi Ori Ori Oval O-ring. WARNING! Thegas ori ce plate iden ce components inthefollowing order. Figure 35. fi fi ce Gasket Rea Before proceeding, con assembly to thefan motor new ori ce ce ConnecttheFan Blower motor wire to thecomputer board. 3 Screws EĂƚƵƌĂů'ĂƐKƌŝĮĐĞ >W'ĂƐKƌŝĮĐĞ ach thegas solenoidvalve NA LP NA LP fi ce iscorrect for thetype 1

on ofthecomponents. fi ca is properly seated and Gas SolenoidValve Assembly on. Assemble the new Assemble thenew fi ce components fi ce assembly fi rm the the rm 3 2 1 turn thewater heater backon. alignment. alignment. front cover inplaceto ensure proper the built-in controller whense removed earlier. Note theplacement of correctly andseated securely. pipe connec them immediately. any cutsornicks are present replace removed earlier. InspecttheO-rings,if shuto as appropriate. Press theOn/O outlet or turning itonat thecircuit breaker, Figure 35: 16 16 15 14 12 18 17 ff valve. Reconnect power to thewater Replace thefront cover and Before proceeding ,take amoment Reinstall thecopper gas pipe Verify proper opera Turn onthegas supplyto the secure withthefour screws to checkallwiringconnec using the16-25Ametal fasteners heater itinto byplugging thewall water heater at themanualgas water heater.

Fn Assembly Fan ons. Make sure allare mated Fan Assembly See Figure 34. on ofthe ff bu ng the the ng on and and on on to MAINTENANCE 2 3 in the 3 re or carbon carbon or re fi on the pipe for clear on the pipe for 2 Remove the 16-25A metal the 16-25A metal Remove 1 the gas valve assembly from assembly from valve the gas c bushing were not le c bushing were 1 Gas valve assembly removal. Gas valve fastener securing the copper fastener

in serious injury result ons can assembly. Inspect the o-ring on assembly. the water heater. Check the gas Check the gas heater. the water Li valve the new gas Install WARNING! The gas valve assembly valve The gas WARNING! 7 8 9 gas inlet mount. inlet gas assembly: valve the gas Replacing gas pipe to the gas valve assembly. assembly. valve the gas pipe to gas reposi Carefully assembly. valve the gas access to must be properly installed to prevent prevent to installed be properly must these follow to Failure leaks. gas instruc explosion, from or death poisoning. monoxide cuts if any assembly, valve the new gas the o-ring replace present are or nicks immediately. Figure 38: Figure the old o-ring ensure assembly to valve and plas Remove the screw securing the wiring securing the screw Remove assembly. valve the gas harness to valve the gas securing the screw Remove See mount. inlet the gas assembly to 38. Figure board, and wiring so that you have clear have you wiring so that and board, assembly. valve the gave access to on. d rrrrrrr w. ooror e to r ove an ec sc

on the surge on the surge s i nn h o Remove and keep and keep Remove RRRRRRemRR t this screw. Connector C e the base to xing plate Built In Controller lat lat lat lalalala fi PPPPPP g P xing plate, computer computer xing plate, fi on. Built-in controller removal. controller Built-in removal. fixing plate box Surge box box Carefully reposi Carefully Box Fixin Box

surge box box surge Remove the screw securing the securing the screw Remove controller and follow it to the it to and follow controller remove the 4 screws securing the securing the 4 screws remove Locate the wire on the built-in on the built-in the wire Locate Use a Phillips-head screwdriver to screwdriver Use a Phillips-head On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 49 Surge Box Fixing Plate Fixing Box Surge 6 5 3 4 computer board. Carefully disconnect Carefully board. computer the computer from controller the built-in on the wiring diagram Reference board. or maintenance 28 in the manual page aside controller the built-in Set sheet. re-installa for cover to the water heater. Set the front the front Set heater. the water to cover re-installa aside for and screws cover Figure 37: Figure Figure 36: Figure of the water heater housing. See Figure housing. See Figure heater of the water 37.

ff the water supply to the gas ff

heater at the manual gas shuto the manual gas at heater heater by unplugging it from by unplugging it from heater or turning it off outlet the wall Shut o Disconnect power to the water the water to power Disconnect

WARNING! WARNING! necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. safety of others, read and follow and follow read of others, safety of these instructions. each step in so could result do to Failure injury or death. personal 2 1 Use a non-contact circuit tester to to tester circuit Use a non-contact before is off power that confirm parts. electrical on or near any working

at the circuit breaker, as appropriate. breaker, the circuit at heater on the water button The power disconnect does NOT and remote must You heater. the water to power the to power disconnect physically heater. water (MV) Assembly Main Gas Valve Valve Main Gas Replacing the the Replacing Removing Removing and NOTICE: DO NOT USE ELECTRIC USE ELECTRIC NOT DO NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TIGHTEN ALL SCREWS TO TIGHTENING. OVER Tools Needed: #2 Phillip’s Head Needed: #2 Phillip’s Tools Screwdriver • To ensure your safety and the safety your ensure • To the skills do not have • If you assembly: valve gas the Removing valve. MAINTENANCE See Figure 36onpage 49. controller to thecomputer board. See Reconnect thewire from thebuilt-in valve. alignment. front cover inplaceto ensure proper the built-in controller whense removed earlier. Note theplacement of mated correctly andseated securely. and pipeconnec 50 • On-Demand Water Heater Handbookfor Service X3PModels Figure 38onpage 49. metal fastener removed earlier. See the copper gas pipeusingthe16-25A replace theo-ringimmediately. Secure pipe, ifany cutsornicks are present . Inspecttheo-ringoncopper gas 49. removed earlier. SeeFigure 38onpage on page 49. the screw removed earlier. SeeFigure 38 its originalloca removed earlier. Restore thewiringto surge box heater housing.Reinstall andsecure the page 49. 12 11 10 15 13 17 18 14 16 Reconnect thecopper gas pipeto Rea Secure thegas valve assemblyto secure itat the newgas valve assemblyat the gas inlet mount at Before proceeding ,take amoment to checkthewiringconnec Return thecomputer board to its original loca Turn onthegas supplyto thewater heater at themanualgas shuto Reconnect power to thewater A the front ofthewater heater. Replace thefront cover and secure withthefour screws ach thebuilt-in controller to ach thewiringharnessand fi xing plate withthescrew on. SeeFigure 37on on. Make sure all are on inthewater 2 with the screw withthescrew ng the the ng 3 using using on on 1 ff

breaker, asappropria outlet orturningitonat thecircuit heater itinto byplugging thewall on. O OVER TIGHTENING. TIGHTEN ALLSCREWSTO PREVENT SCREWDRIVERS ORDRILLS,HAND NOTICE: DONOT USEELECTRIC magnetic tip),Pliers. Screwdriver (16”orlonger with Screwdriver, #2Phillip’s Head Tools Needed:#2Phillip’s Head Removing theprimaryheat exchanger: • Ifyou donothave theskills • To ensure your safety andthe Exchanger Primary Heat Replacing the and Removing power to thewater heater. You must and remote doesNOT disconnect The power button onthewater heater at thecircuit breaker, asappropriate. 1 ff 19 personal injuryordeath. Failure to dosocouldresult in each step oftheseinstructions. safety ofothers, read andfollow bu qualified service technician.qualified service proceed. Seekassistance from a procedure correctly, donot necessary to complete this WARNING! Disconnect power to thewater the wall outlet orturningitoff heater itfrom byunplugging on to turnthewater heater back Verify proper opera water heater.

te. Pr ess theOn/ on ofthe drain before proceeding. heater. Allowthesystem to completely on thebo and opentheplas Place abucket underthewater heater shuto water heater. physically disconnect power to the cover andscrews asidefor re-installa cover to thewater heater. Set thefront working onornearany electrical parts. confirm that power isoff before Use anon-contact circuit tester to tray. Slidetherain protec plas the screw andbracket securingthe right sideofthewater heater. Remove to thecopper gas pipe. heater to accessthecable connec and plas installa Keep thescrew andbracket for re- installa the rain protec the water heater. Keep thescrew with 4 3 2 7 5 6 c housingfor thecomputer board. ff valve. Use aPhillips-headscrewdriver to Shut o Shut o Locate theplas Remove thescrew securingthe heater anddrain thesystem. water heater at themanualgas remove the4 screws securingthe le board housingonthebo Remove thewhite plas on. Slidethecomputer board on. clips securingthevarious cables c housingoutfrom thewater sideoftherain protec om le om ff ff thegas supplyto the water to thewater c drain portlocated sideofthewater on tray for re- on plate from c computer c c cable cable c ons. om om on. on on MAINTENANCE

ff ons). Move ons). ng the copper 45on. See Figure c connector. Both c connector. Flame Rod Connector. Flame Rod

Primary Heat Exchanger Outlet. Exchanger Primary Heat Inlet Thermistor Connector. Thermistor Inlet

Inlet Thermistor Connector Inlet Thermistor Fuse (O.H.C.F.) # 413 wires at the at # 413 wires Fuse (O.H.C.F.) under the407). It is located connec fasteners Disconnect the Over Heat Cuto Heat the Over Disconnect (# thermistor the inlet Disconnect the 16-25A metalDisconnect c connector and the Hi Limit Switch (# and the Hi Limit Switch c connector 16-25A Metal Fastener Primary Heat Outlet Exchanger 18 16 17 connectors are located on the same blue located are connectors side of the right at located are They cable. Exchanger. the Primary Heat 721) wires at the plas at 721) wires 51. on page the pipe aside and keep the metal the pipe aside and keep re-installa for fasteners plas 44. See Figure exchanger. heat secondary outlet exchanger the primary heat pipe to (Reference tee outlet (# 468) and the water instruc C in maintenance Joint 45: Figure Figure 43: Figure 44: Figure ce: ame rod on. fl c connector e Thermistor nn Co Heat Exchanger Heat d Ro 16-25A Fastener e ws re am Sc Flame Rod Connector Flame Rod Fl Copper Gas Pipe r to Gas Pipe and Fan Motor Assembly Motor Gas Pipe and Fan Disconnect for Heat Exchanger Thermistor. Exchanger Heat for Disconnect on. Press the small tab in the the small tab on. Press

joining the purple igniter rod wires. rod joining the purple igniter assembly from the water heater the water assembly from 42. (# 411). Figure cable thermistor connector (Yellow wire). No wire). (Yellow connector Disconnect the plas Disconnect the Disconnect Remove the complete fan motor fan the complete Remove exchanger the heat Disconnect Mo ame rod connector uses a special connector ame rod fl n On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 51 Press small Press tab. FanFa Motor Screws 14 15 12 13 mixing chamber assembly. See Figure 41. See Figure assembly. mixing chamber the it. See release to of the connector center 43. Figure and set it aside for re-installa it aside for and set Figure 42: Figure Figure 41: Figure removal. connec fy ables the two R,W,BK Pressure Sensor Connector c housing c on. Remove Remove on. Y,O,W,R,BR Connector Air Damper Fan Motor Assembly Wire Connections Assembly Wire Motor Fan Computer Board Bracket. Board Computer

controller and follow it to the it to and follow controller Locate the wire on the built-in on the built-in the wire Locate on. fasteners on both ends of the fasteners on the fan motor assembly to their assembly to motor on the fan cable from the computer board. the computer from cable Remove the 16-25A metal the 16-25A metal Remove Locate and follow the three c the three and follow Locate Disconnect the black fan motor the black fan Disconnect c connectors. Disconnect and move Disconnect c connectors. R,LB,G,B Gas Solenoid 8 9 11 10 Valve Connector Valve cables. screws securing the fan motor to the to motor securing the fan screws them aside. Reference Figure 40 to iden 40 to Figure them aside. Reference back into the water heater to prevent prevent to heater the water back into on the cables. unnecessary tension computer board. Carefully disconnect Carefully board. computer the computer from controller the built-in on the wiring diagram Reference board. sheet. 28 or in the maintenance page re- aside for controller the built-in Set installa copper gas pipe (# 104) and set them pipe (# 104) and set gas copper re-installa aside for Figure 40: Figure plas Reference the wiring diagram on page wiring diagram the Reference Slide sheet. 28 or in the maintenance and plas board the computer Figure 39: Figure MAINTENANCE 52 • On-Demand Water Heater Handbookfor Service X3PModels secondary heat exchanger. Theconnec nection. Figure 47: Figure 47. fastener asidefor re-installa moved asideto allowaccess.Set themetal pipes disconnected insteps 17and18 restricted soyou willneedto have the secondary heat exchanger. Spaceis disconnect thecopper pipefrom the Remove the16-25Ametal fastener and secondary heat exchanger inlet (#466). the copper pipeconnected to the Figure 46: installa 465). Set thefastener asidefor re- pliers to move theclamp.SeeFigure 48. uses acompression clampandwillrequire 21 20 19 16-25 Metal -2 FastenerFasten 5 M Disconnect the rubber drain tube Disconnect therubberdrain tube On thele Disconnect the6-15metal fastener (# 416)from thebo secondary heat exchanger, locate from the smallcopper drain pipe(# on. Figure 46.

CopperDrain Pipe. Secondary Heat Exchanger Inlet Con- en e ta Fastener 6-15 Metal a ere l -back sideofthe Drain Pipe Copper ExchangeEEx Inlet SecondarySSe Heat ch co h ondary o an om right of the om right ofthe g e I on. See See on. on on Exchanger Inlet Pipe. Figure 49: Figure 48: heater enclosure. SeeFigure 50. the exhaust ductto thetop ofthewater Remove andset asidethescrew securing when itisbeingremoved. SeeFigure 49. catching ontheheat exchanger assembly heater andwires asideto prevent it Exchanger inlet pipe.Move theblock 23 22 Inlet I Primary HeatP Exchanger n rimary Heat Exc le t Disconnect theexhaust thermistor Disconnect theceramic block (# 718) and move the wires aside. (# 718)andmove thewires aside. heater from thePrimaryHeat

Ceramic blockheater onPrimaryHeat Drain line. CeramicC BlockHeater e r a mi i c B lock h an CompressionCompressi Clamp H g Drain Line er e ono n C l am p placed onasecure surface, take note not The heat exchanger assembly shouldbe the bo heat exchanger base, its disconnect theplas front ofthewater heater slowlylower itto exchanger assemblybaseisclearofthe the heat exchanger. Once theheat water pipingandothercomponents under exchanger assembly. Whilesuppor aside, begintheremoval oftheheat 51. Oncebothscrews are removed andset inches ormore must be screwdriver withalength ofat least 8 screws, amagne securing itto theenclosure. To reach the hand, whenremo assembly must thenbesupported by heater enclosure. Theheat exchanger support bracket to thebackofwater and set asidethe4screws securingthe assembly duringitsremoval. Remove will drain from theheat exchanger under thewater heater assomewater Cover electronics andanything directly Figure 50: 24 fi

ng at thetop ofthewater heater. NOTICE: Read thisstep carefully before performing any ac om. Usecare notto damage the

Ehut Thermistor. Exhaust zed ving the two screws ving thetwo screws c exhaust ductfrom lt itoutward from used. p Phillips-head Phillips-head p Sc E Screw Exhaust Duct x r ha Thermistor Exhaust ew See Figure See Figure us s t ng the DDu ons. ons. ct MAINTENANCE on on.

l a et M r e A 16-25A Metal 16-25A Metal Fastener on and orienta on and d RoRRR rrr r om of the Primary Heatom of the Primary ,ĞĂĚĞƌŽŶŶĞĐƟŽŶƐ ttetetete i Header Connection Removal Connections. Rod Igniter

nninini bo securing the support bracket and securing the support bracket wires from the igniter rod. rod. the igniter from wires Place new the gasket on the Place new the gasket Remove the three screws screws the three Remove Disconnect the green and gray gray and the green Disconnect g Igniter Rod Igniter Ig WARNING! The heat exchanger exchanger The heat WARNING! 31 30 29 of the two metal compression brackets brackets compression metal of the two (# 421 & #422). Exchanger (# 401). If any cuts or any other cuts or any (# 401). If any Exchanger set them aside for re-installa them aside for set to installed be properly assembly must leaking. from gases exhaust prevent carbon cause can follow to Failure poisoning or death. monoxide Unbundle the green wire from the metal the metal from wire Unbundle the green 54. guides. See Figure cable 54: Figure nine screws the remaining Remove (# exchanger securing the primary heat (# exchanger heat the secondary 401) to the loca 418). Note exchanger: heat the primary Replacing Figure 53: Figure c on ca fi bolt and ern on the Check the gaskets to Check the gaskets e: Tighten e: Tighten on of the elements. Nm). speci a torque ons to reassembly. on for assembly and burner mixing elements in the following order, order, following in the elements removed. Turn it over to view the to it over Turn removed. Carefully place the burnerCarefully Assemble the new burner Once the burner plate has beenburner plate Once the On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 53 WARNING! The burner assembly WARNING! Burner Mixing Chamber. Mixing Chamber Gasket Mixing Chamber Gasket Burner Gasket Burner (Mesh Metal) 1 28 27 26 2 4 3 primary heat exchanger will only line up will only line exchanger primary heat and burner mixingwith burner assembly this Note properly. chamber if it is oriented orienta Note the orienta Note All holes will line up if it is correctly oriented. exchanger. the primary heat chamber onto bolts and nutswith the twelve Secure Not earlier. removed reference Figure 14. Figure reference nut connec burner assembly and gaskets. Use a plas and gaskets. burner assembly scraper to remove the old burner assembly remove to scraper material gasket Clean any and gaskets. the burner mixing on remain may that pa The hole NOTICE: chamber. of 31 in-lbf (3.5 make sure no gaps are present. present. are no gaps sure make must be properly installed to prevent prevent to installed be properly must to leaking. Failure from gases exhaust monoxide carbon cause can follow poisoning or death. ached. ll a ll sssssss Heat Exchanger Screws Exchanger Heat

Burner and gasket assembly order. Burner and gasket wsws s are ons that

bolts and nuts securing the top ofbolts and nuts securing the top fastener securing the copper pipecopper securing the fastener Remove and set aside the twelve and set Remove Remove the 16-25A metal metal the 16-25A Remove e r 1 2 3 4 Screws Sc 25 25 Figure 52: Figure the burner plate to the primary heat the primary to the burner plate 4. See Figure exchanger. Removing the burner plate (Steps 25 - 28): (Steps Removing plate the burner to the primary heat exchanger (# 467). (# 467). exchanger the primary heat to 53. See Figure Figure 51: Figure to damage the various piping and wiring piping the various damage to connec MAINTENANCE 54 • On-Demand Water Heater Handbookfor Service X3PModels To assist withinstalla primary heat exchanger. See through thecable guidesonthefront ofthe Figure 53. are present replace itimmediately. See Inspect theO-ringsifany cuts ornicks fastener. Usetheprovided O-ring. Hand Secondary Heat Exchanger. NOTICE: secure thePrimaryHeat Exchanger to the compression brackets (#421Ʀ) Using theninescrews andtwo metal Check alignment ofthescrew holes. top oftheSecondary Heat Exchanger. the newPrimaryHeat Exchanger to the CenterService to order anewone.A a newgasket must beused.Contact the issues are present donotusethegasket, screws removed earlier. primary heat exchanger withthethree assembly a connec the screws that secures theside Re-a not useanelectricscrewdriver ordrill. Li four screws that secure the moun screw to thesidebracket. Next install the secure theassembly. Install theremaining with thescrew already a Figure 51.Usethemagne screws securingitto theenclosure. See supported byhand, whileinst exchanger assemblymust thenbe water heater enclosure. Theheat with theexhaust portonthetop ofthe top oftheplas the top backandslideitinup.The bracket to thebackofwater heater p screwdriver andwithineasy reach. 34 33 32 theheat exchanger assemblyand ach thesupportbracket to the Rea Reconnect thecopper pipe before performing any ac the igniter rod. Route thegreen wire (# 467)usingthe16-25Ametal ghten allscrew connec NOTICE: Read thisstep carefully on oftheheat exchanger achthegreen andgray wires to ffi xed to thelongmagne c exhaust ductwillmate on have oneof ffi Figure 54. c screwdriver screwdriver c xed to itto alling the alling the ons, do do ons, ons. ach ach ng ng lt lt c

page 51. screws removed earlier. assembly (#112). placement. 28 orinthemaintenance sheet for Reference thewiringdiagram on page page 52. Exchanger inlet pipe.SeeFigure 49on earlier. SeeFigure 46on page 52. the 16-25Ametal fasteners removed present replace themimmediately. Use the O-rings,ifany cutsor nicks are outlet and thewater outlet tee. earlier. SeeFigure 46 onpage 52. Use the6-15metal fastener removed nicks are present replace itimmediately. ifany O-ring. InspecttheO-ring, cutsor clock posi sec the fastener, posi 16-25A metal fastener. Whenplacing exchanger inlet. SeeFigure 53.Usethe correct orienta Reference SeeFigure 43onpage 51.for the specialtab must befacing outward. heat exchanger. See enclosure. 43 42 41 40 39 38 37 36 35 on) ofthefastener to theten o’ Reconnect theheat exchanger Reconnect the ConnecttheFan Blower motor Rea Reconnect theceramic block Reconnect thecopper pipe(#468) Reconnect thesmallcopper drain Reconnect therubberdrain line Reconnect thecopper pipe assembly to the (Yellow wire). Whenconnec thermistor connector. SeeFigure 42 wire to thecomputer board. heater from thePrimaryHeat to theprimary heat exchanger pipe (#465). to thebo (# 466)to thesecondary heat on. ach thefan blower on. See Figure 47. om ofthesecondary Secure itwiththetwo Figure 48. on thetop ( fl Use theprovided ame rod connector See Figure 41 on See Figure 41on mixing chamber mixing chamber Inspect Inspect fl ng ng at at loca 28 orinthemaintenance sheet for plug Reference thewiringdiagram onpage controller to thecomputer board. Reconnect thewire from thebuilt-in on page 51. immediately. SeeFigure 41onpage 51. any cutsornicks are present replace them removed earlier. InspecttheO-rings,if plas exchanger. SeeFigure 44onpage 51. the samebluecable. Switch. Bothconnectors are located on reconnect theexhaust thermistor. using thescrew removed earlierand series ofver Figure 39onpage 51. bracket andscrew removed earlier. See water heater. Secure it inplacewiththe page 51.to iden pipe connec side ofthewater heater. 48 47 46 45 44 54 53 52 51 50 49 c connectors. SeeFigure 40on on. Reinstall thecopper gas pipeusing Reconnect thethree cables on Reconnect theinlet thermistor. Itis Reconnect theOver Heat Cuto Reconnect theigniter rod Before proceeding ,take amoment Secure the exhaust ductto thetop Re-install therain protec Use thewhite plas A Slide theplas the front ofthewater heater. the 16-25Ametal fasteners the fan motor assemblyto their located underthesecondary heat Fuse (O.H.C.F.) andtheHiLimit connector (purplewires). to checkallwiringconnec of thewater heater enclosure removed earlierto organize the computer board backinto the using thescrew removed earlier. ach thebuilt-in controller to ons. Make sure allare mated cal cables alongtheright fy cables. c housing with the c housingwiththe c cable clips on tray on and and on ff

MAINTENANCE om ables ons. c cable c housing c c computer c connectors. c housing out from the water the water c housing out from Computer Board Bracket. Board Computer

on. Slide the computer board board the computer on. Slide on. on. clips securing the various cables the various clips securing the bo housing on board controller and follow it to the it to and follow controller board. the computer from cable motor the fan from coming Locate the wire on the built-in on the built-in the wire Locate motor the black fan Disconnect c the three and follow Locate Remove the white plas white the Remove the plas Locate c housing for the computer board. board. the computer c housing for 8 9 9 6 7 Keep the screw and bracket for re- for and bracket the screw Keep installa and plas connec access the cable to heater installa back into the water heater to prevent prevent to heater the water back into on the cables. unnecessary tension to the copper gas pipe. gas the copper to right side of the water heater. Remove Remove heater. side of the water right securing the bracket and the screw plas computer board. Carefully disconnect Carefully board. computer the computer from controller the built-in on the wiring diagram Reference board. sheet. 28 or in the maintenance page re- aside for controller the built-in Set installa on page the wiring diagram Reference Slide sheet. 28 or in the maintenance and plas board the computer plas their assembly to them aside. and move Disconnect Figure 55: Figure on on. from on plate

on tray for re- for on tray side of the water side of the water c drain port located port located c drain water to the water water the to water the gas supply to the supply to the gas ff ff om le side of the rain protec side of the rain le remove the 4 screws securing the the 4 screws remove heater by unplugging it from the by unplugging it from heater the at or turning it off outlet wall water heater at the manual gas the manual gas at heater water heater and drain the system. the system. and drain heater Remove the screw securing the the screw Remove Shut o Shut o to Use a Phillips-head screwdriver Disconnect power to the water the water to power Disconnect valve. ff On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 55 necessary to complete this this complete to necessary do not correctly, procedure a from Seek assistance proceed. qualified service technician. 4 5 2 3 1 the water heater. Keep the screw with the screw Keep heater. the water protec the rain tray. Slide the rain protec Slide the rain tray. cover to the water heater. Set the front the front Set heater. the water to cover re-installa aside for and screws cover circuit breaker, as appropriate. The power appropriate. as breaker, circuit and remote heater on the water button the water to power disconnect does NOT disconnect physically must You heater. heater. the water to power Use a non-contact circuit tester to to tester circuit Use a non-contact before is off power that confirm parts. electrical on or near any working Tools Needed: #2 Phillip’s Head Needed: #2 Phillip’s Tools Head #2 Phillip’s Screwdriver, with or longer (16” Screwdriver tip), Pliers. magnetic USE ELECTRIC DO NOT NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TO TIGHTEN ALL SCREWS TIGHTENING. OVER shuto completely to Allow the system heater. proceeding. before drain on the bo Place a bucket under the water heater heater under the water Place a bucket and open the plas

ff ng the on of the

ons by restoring water to the to water by restoring ons with a full stream. ows water heater at the manual gas the manual gas at heater water heater. water water heater at the manual gas the manual gas at heater water the wall by plugging it into heater secure with the four screws screws with the four secure water heater, check the piping check heater, water Verify proper opera proper Verify Turn on the gas supply to the supply to on the gas Turn Turn on the gas supply to the supply to on the gas Turn Replace the front cover and cover the front Replace Before restoring power to the to power restoring Before Reconnect power to the water the water to power Reconnect fl valve. valve. ff ff

back on. heater turn the water on to l it l WARNING! WARNING! safety of others, read and follow and follow read of others, safety of these instructions. each step in do so could result to Failure injury or death. personal 60 59 58 57 56 55

system and check for any leaks. Allow a leaks. any and check for system pressurize. to system the for moments few a hot Open immediately. leaks any Correct run to and allow the water faucet water un Exchanger Secondary Heat Secondary Heat and Replacing and Replacing bu Removing shuto shuto the circuit or turning it on at outlet the On/O Press as appropriate. breaker, front cover in place to ensure proper proper ensure to in place cover front alignment. removed earlier. Note the placement of the placement Note earlier. removed when se controller the built-in connec correctly and seated securely. and seated correctly • If you do not have the skills do not have • If you • To ensure your safety and the safety your ensure • To MAINTENANCE 56 • On-Demand Water Heater Handbookfor Service X3PModels tor. Figure 58: 58. and set it asidefor re-installa removal. Figure 57: aside for re-installa copper gas pipe(#104)andset them Figure 56: Reference Figure 2to iden mixing chamberassembly. SeeFigure 57. screws securingthefan motor to the Valve Connector 12 11 10 Fan Motor Screws Motor Fan Fa Gas Solenoid R,LB,G,B n Mo Disconnect theheat exchanger Remove thecomplete fan motor Remove the16-25Ametal thermistor cable (#411).SeeFigure assembly from thewater heater fasteners onbothendsofthe

Disconnect for Heat Exchanger Thermis- GasPipeandFan Motor Assembly

Fan Motor AssemblyWire Connections to r Copper GasPipe Sc re ws 16-25A Fastener Air Damper Connector Y,O,W,R,BR on. Remove Heat Exchanger Thermistor fy cables. on. Connector Sensor Pressure R,W,BK the two the two plas connec Figure 60: Figure 59: 721) wires at theplas the secondary heat exchanger. SeeFigure 60. Figure 59onpage 56. center oftheconnector to release it.See for re-installa pipe asideandkeep themetal fasteners (# 468)andthewater outlet tee. Move the pipe to theprimaryheat exchanger outlet the PrimaryHeat Exchanger. cable. They are located at theright sideof connectors are located onthesameblue 17 16 15 14 13 tab. Press small c connector and the Hi Limit Switch (# c connector andtheHiLimitSwitch (# fl ame rod connector usesaspecial Disconnect the 16-25A metal Disconnect the16-25Ametal Disconnect theinlet thermistor (# Disconnect theOver Heat Cuto Disconnect the Disconnect theplas Fuse (O.H.C.F.) #413wires at the connector (Yellow wire). No fasteners connec 407). Itislocated underthe joining thepurpleigniter rod wires.

on. Press thesmalltab inthe Inlet Thermistor Connector.

Inlet Thermistor Connector FlameRod Connector. Flame RodF Connector la on. SeeFigure 61. m e R od C c connector. Both o nn ng thecopper e c connector connector c fl ame rod rod ame ce: ce: ff

installa 465). Set thefastener asidefor re- Figure 61: Figure 63: fastener asidefor re-installa moved asideto allowaccess.Set themetal pipes disconnected insteps 17and18 restricted soyou willneedto have the secondary heat exchanger. Spaceis disconnect thecopper pipefrom the Remove the16-25Ametal fastener and secondary heat exchanger inlet (#466). the copper pipeconnected to the Figure 62: Connection. Figure 63. 18 19 16-25 Metal Exchanger Outlet Primary Heat Fastener 16-25A Metal -2 FastenerFastener 5 M Disconnect the6-15metal fastener On thele from the smallcopper drain pipe(# secondary heat exchanger, locate on. SeeFigure 62.

Primary Heat Exchanger Outlet. CopperDrain Pipe. Secondary Heat Exchanger Inlet ene e t a er l Fastener 6-15 Metal -back sideofthe EEx Exchanger Inlet SecondarySSe Heat Drain Pipe Copper c c h ondary o an g er on. See See on. MAINTENANCE on. l a t e r M e A 16-25A Metal 16-25A Metal Fastener d RoRRR rrrr r ,ĞĂĚĞƌŽŶŶĞĐƟŽŶƐ sssssss Heat Exchanger Screws Exchanger Heat Removal Header Connection Connections. Rod Igniter

ttetetete wsws i securing the support bracket and securing the support bracket wires from the igniter rod. rod. the igniter from wires fasteners securing the copper fasteners Remove the three screws screws the three Remove Disconnect the green and gray and gray the green Disconnect Remove the 16-25A metal Remove e nninini r g Igniter Rod Igniter Ig Screws Sc 26 25 24 set them aside for re-installa them aside for set securing the screws the ten Remove Unbundle the green wire from the metal the metal from wire Unbundle the green 69. guides. See Figure cable inlet tube (#467) to the heat exchangers. exchangers. heat the tube (#467) to inlet only replacing are 68. If you See Figure 32. step to tube, proceed the inlet step. the next to Otherwise, proceed 68: Figure 69: Figure Figure 67: Figure ct ons. ng the ng DDDDDDDuDuDuD ttttttt s See Figure us ew Exhaust Exhaust Thermistor ha r x ached. E Sc Exhaust Duct Exhaust Screw p p Phillips-head lt it outward from lt it outward ll a ll be used. be used. c exhaust duct from c exhaust ving the two screwsving the two zed zed Exhaust Exhaust Thermistor. s are ons that

om. Use care not to damage the damage not to om. Use care before performing any ac any performing before NOTICE: Read this step carefully carefully step this Read NOTICE: ng at the top of the water heater. heater. of the water the top ng at

On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 57 fi 23 its water piping and other components under piping and other components water Once the heat exchanger. the heat assembly base is clear of the exchanger it to slowly lower heater of the water front the plas disconnect The heat exchanger assembly should be exchanger The heat not note taking surface, placed on a secure piping and wiring the various damage connec the bo heat exchanger base, exchanger heat 67. Once both screws are removed and set removed are 67. Once both screws of the heat aside, begin the removal While suppor assembly. exchanger screwdriver with a length of at least 8 least of at with a length screwdriver must inches or more Cover electronics and anything directly directly and anything electronics Cover as some water heater under the water exchanger heat the from will drain Remove assembly during its removal. securing the aside the 4 screws and set the back of the water to support bracket exchanger The heat enclosure. heater by then be supported assembly must hand, when remo the reach To the enclosure. securing it to a magne screws, Figure 66: Figure p on am l C n on io of theom right Drain Line Drain e er g Compression Clamp Compression Compress H an h lock B cc iii mimimimi a r e Ceramic Block Heater Ceramic C Ceramic block heater on Primary Heat block heater Ceramic Drain line. Drain

(# 718) and move the wires aside. the wires (# 718) and move heater from the Primary Heat from heater (# 416) from the bo (# 416) from Disconnect the exhaust thermistor the exhaust Disconnect Disconnect the ceramic block the ceramic Disconnect Disconnect the rubber drain tube the rubber drain Disconnect t t t t t t le rimary Heat Exc rimary Heat n Primary Heat Exchanger Primary Heat P I Inlet 22 21 20 secondary heat exchanger. The connec exchanger. heat secondary and will require clamp uses a compression 64. the clamp. See Figure move to pliers Exchanger Inlet Pipe. Inlet Exchanger Remove and set aside the screw securing aside the screw and set Remove of the water the top duct to the exhaust 66. See Figure enclosure. heater Figure 65: Figure Exchanger inlet pipe (# 467). Move the pipe (# 467). Move inlet Exchanger it prevent aside to and wires block heater assembly exchanger on the heat catching 65. See Figure when it is being removed. Figure 64: Figure MAINTENANCE installa assembly andscrew asidefor re- Carefully set theigniter monoxide poisoningordeath. Failure to follow can cause carbon prevent exhaust gases from leaking. assembly must beproperly installed to 58 • On-Demand Water Heater Handbookfor Service X3PModels correct orienta them immediately. See any cutsornicks are present replace removed earlier. InspecttheO-rings,if heat exchanger usingthescrews for any cutsorimperfec down onasolidsurface. Checkthegasket exchanger: Replacing thesecondaryheat (# 431)to thesecondary heat exchanger. the loca secondary heat exchanger (#418).Note primary heat exchanger (#401)to the earlier. exchanger usingthescrew removed seated. and checkto make sure allscrews are fully removed earlier. Hand exchanger withtheeighteen screws exhaust ductto thesecondary heat screw holealignment. Secure theplas secondary heat exchanger andverify the gasket (#432)onthebo #422). metal compression brackets (#421& 32 31 30 29 28 27 WARNING! Theheat exchanger With the new secondary heat With thenewsecondary heat Inspect thegasket (#420) Reinstall bothheaderconnec Reinstall theigniter Remove theeighteen screws Remove thescrew securingthe exchanger (#418)res (# 472Ǚ)to thesecondary securing theplas igniter (# 711)to thesecondary heat on. on. on andorienta on ofthe fi xing plate (#711). ons. Place the new ons. Placethenew ghten all screws screws all ghten om of the new om ofthenew cexhaust duct on ofthetwo fi Figure 68 for Figurefor 68

ngs. ngs. fi fi xn plate xing xn plate xing ng upside upside ng ons ons c screws removed earlier. primary heat exchanger withthethree Hand Secondary Heat Exchanger. NOTICE: Primary Heat Exchanger to the brackets (#421Ʀ)secure the ten screws andtwo metal compression alignment ofthescrew holes.Usingthe the Secondary Heat Exchanger. Check Primary Heat Exchanger to thetop of Re-a not useanelectricscrewdriver ordrill. gaskets where they lineup.A make sure there isn’tagap between the This gasket is2pieces.Take care to cuts orany otherissuesare present. heat exchanger (#401).Replace it if any a To assist withinstalla on page 57. primary heat exchanger. See through thecable guidesonthefront ofthe Figure 68onpage 57. are present replace itimmediately. See Inspect theO-ringsifany cuts ornicks fastener. Usetheprovided O-ring. connec the screws that secures theside assembly a Li top oftheplas the top backandslideitinup.The magne See Figure 67onpage 57.Usethe screws securingitto theenclosure. See supported byhand, whileinst exchanger assemblymust thenbe water heater enclosure. Theheat with theexhaust portonthetop ofthe p screwdriver andwithineasy reach. 35 34 33 ached to thebo the heat exchanger assemblyand ach thesupportbracket to the ghten allscrew connec Rea Reconnect thecopper pipe before performing any ac the igniter rod. Route thegreen wire (# 467)usingthe16-25Ametal c screwdriver withthescrew NOTICE: Read thisstep carefully on oftheheat exchanger achthegreen andgray wires to ffi xed to thelongmagne c exhaust ductwillmate om oftheprimary on have oneof See Figure 69 alling the alling the ach the the ach ons, do do ons, ons. lt lt c

page 56. screws removed earlier. assembly (#112). earlier. SeeFigure 62on page 56. Use the6-15metal fastener removed nicks are present replace itimmediately. ifany O-ring. InspecttheO-ring, cutsor fastener to theten o’clockposi posi fastener. Whenplacingthefastener, page 56. exchanger inlet. See placement. 28 orinthemaintenance sheet for Reference thewiringdiagram on page page 57. Exchanger inlet pipe.SeeFigure 65on earlier. SeeFigure 61on page 56. the 16-25Ametal fasteners removed present replace themimmediately. Use the O-rings,ifany cutsor nicks are outlet and thewater outlet tee. heat exchanger. the specialtab must befacing outward. of thewater heater enclosure. secure themoun bracket. Next install thefour screws that Install theremaining screw to theside already a 38 37 36 43 42 41 40 39 on thetop ( Reconnect thesmallcopper drain Reconnect therubberdrain line Reconnect thecopper pipe Reconnect the ConnecttheFan Blower motor Rea Reconnect theceramic block Reconnect thecopper pipe(#468) assembly to the pipe (#465). to thebo (#466) to thesecondary heat (Yellow wire). Whenconnec wire to thecomputer board. heater from thePrimaryHeat to theprimary heat exchanger ffi xed to itto secure theassembly. Use the16-25Ametal ach thefan blower ng bracket to theback om ofthesecondary Secure itwiththetwo fl a sec at fl Use theprovided ame rod connector See Figure 63 on See Figure 63on See Figure 57 on See Figure 57on mixing chamber mixing chamber on) ofthe on. on. Inspect Inspect ng ng MAINTENANCE on.

the gas supply to the supply to the gas ff igniter rod connectors. See Figure connectors. rod igniter Disconnect the two wires from the from wires the two Disconnect remove the 4 screws securing the the 4 screws remove heater by unplugging it from by unplugging it from heater or turning it off outlet the wall water heater at the manual gas the manual gas at heater water Shut o to Use a Phillips-head screwdriver Disconnect power to the water the water to power Disconnect valve. ff necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. each step of these instructions. of these instructions. each step in result do so could to Failure injury or death. personal 4 2 3 1

cover to the water heater. Set the front the front Set heater. the water to cover re-installa aside for and screws cover 70. at the circuit breaker, as appropriate. as appropriate. breaker, the circuit at heater water on the button The power disconnect does NOT and remote must You heater. the water to power the to power disconnect physically heater. water to tester circuit Use a non-contact before is off power that confirm parts. electrical on or near any working • If you do not have the skills do not have • If you Head Needed: #2 Phillip’s Tools Screwdriver. USE ELECTRIC DO NOT NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TIGHTEN ALL SCREWS TO TIGHTENING. OVER shuto

ff on and ng the on of the ons. Make sure all are mated all are sure ons. Make ons by restoring water to the to water by restoring ons with a full stream. ows heater by plugging it into the wall by plugging it into heater water heater at the manual gas the manual gas at heater water heater. water secure with the four screws screws four with the secure the manual gas at heater water to check all wiring connec to check the piping heater, water Turn on the gas supply to the supply to on the gas Turn opera proper Verify Replace the front cover and cover the front Replace the supply to on the gas Turn Before proceeding , take a moment , take proceeding Before the to power restoring Before Reconnect power to the water the water to power Reconnect fl valve. valve. ff ff back on. heater turn the water on to l it l WARNING! WARNING! On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 59 safety of others, read and follow and follow read of others, safety 61 62 63 59 60 57 58 correctly and seated securely. and seated correctly pipe connec system and check for any leaks. Allow a leaks. any and check for system pressurize. to system the for moments few a hot Open immediately. leaks any Correct run to and allow the water faucet water un bu outlet or turning it on at the circuit or turning it on at outlet the On/O Press as appropriate. breaker, shuto removed earlier. Note the placement of the placement Note earlier. removed when se controller the built-in shuto connec proper ensure to in place cover front alignment. • To ensure your safety and the safety your ensure • To Removing Removing and the Replacing - Flame Igniter Assembly Rod reconnect the exhaust thermistor. See thermistor. exhaust the reconnect 57. 66 on page Figure

ff on. on tray tray on See Figure c cable clipsc cable See c connectors. c housing with the See See Figure 57 onSee See Figure onnector. onnector. cal cables along the right cables cal ach the built-in controller to controller ach the built-in using the screw removed earlier. earlier. removed using the screw of the water heater enclosure heater of the water removed earlier to organize the organize earlier to removed computer board back into the back into board computer using the 16-25A metal fasteners fasteners using the 16-25A metal located under the secondary heat under the secondary located motor the fan from coming connector (purple wires). connector thermistor c thermistor the Hi Limit and Fuse (O.H.C.F.) the front of the water heater. heater. of the water the front Re-install the rain protec the rain Re-install the top duct to the exhaust Secure Use the white plas Use the white A Slide the plas Reinstall the copper gas pipe gas the copper Reinstall Reconnect the inlet thermistor. It is thermistor. the inlet Reconnect cables the three Reconnect Reconnect the igniter rod the igniter Reconnect Cuto Heat the Over Reconnect Reconnect the heat exchanger exchanger the heat Reconnect on. 56 55 52 51 50 49 48 47 45 46 44 side of the water heater. heater. side of the water using the screw removed earlier and removed using the screw series of ver water heater. Secure it in place with the Secure heater. water See earlier. removed and screw bracket 55. 55 on page Figure page 56. page removed earlier. Inspect the O-rings, if earlier. removed replace present are or nicks cuts any them immediately. exchanger. See Figure 60 on page 56. 60 on page See Figure exchanger. their plas assembly to 58 on page 56. 58 on page 56. 56 on page Figure Switch. Both connectors are located on located are Both connectors Switch. the same blue cable. Reference Figure 59 for correct orienta correct 59 for Figure Reference Reconnect the wire from the built-in the built-in from the wire Reconnect board. the computer to controller on page the wiring diagram Reference plug for sheet. 28 or in the maintenance loca MAINTENANCE 60 • On-Demand Water Heater Handbookfor Service X3PModels aside for re-installa primary heat exchanger. Set thesescrews monoxide poisoning ordeath. Failure to follow can cause carbon prevent exhaust gases from leaking. assembly must beproperly installed to correct orienta heater exchanger moun debris/gasket material from theprimary Assembly: Removing theIgniter -FlameRod Figure 71: Figure 70: connec the Figure 71. center oftheconnector to release it.See /ŐŶŝƚĞƌZŽĚŽŶŶĞĐƟŽŶƐ 8 7 6 WARNING! Theigniter - tab. Press small fl 5 ame rod connector usesaspecial Install thenewigniter - Before installing thenewigniter - assembly, reference Figure 70for fl Remove the4screws securingthe igniter - ame rod assemblyremove any

on. Press thesmalltab inthe Igniter wires andflamerod wires.

FlameRod Connector. Disconnect the connector (Yellow wire). No ĚŽŶŶĞĐƟŽŶƐ Flame RodFla Connector on. Secure withthefour fl ame rod assembly to the ame rod assemblyto the m e on. SeeFigure 70 &ůĂŵĞZŽĚŽŶŶĞĐƟŽŶ R od ng point. C o nn fl ame rod rod ame e fl ame rod ame fl ame rod rod ame ce: ce: appropriate connec leaks are detected, re-seat the bu sealed. the gasket isnotpinchedandfully screws removed earlier. Checkto ensure Thermistors Replacing The And Removing Screwdriver Tools Needed: #2Phillip’s Head • Ifyou donothave theskills • To ensure your safety andthe alignment. alignment. front cover inplaceto ensure proper the built-in controller whense removed earlier. Note theplacement of shuto correctly andseated securely. pipe connec breaker, as appropriate. Press theOn/O outlet or turningitonat thecircuit 13 12 11 10 9 personal injuryordeath. Failure to dosocouldresult in each step oftheseinstructions. safety of others, read andfollow qualified service technician.qualified service proceed. Seekassistance from a procedure correctly, donot necessary to complete this WARNING! on to turnthewater heater backon. ff valve andcheckfor leaks. Ifany Reconnect power to thewater Replace thefront cover and Turn onthegas supplyto the Before proceeding ,take amoment Verify proper opera water heater. secure withthefour screws water heater at themanualgas to checkallwiringconnec heater itinto byplugging thewall ons. Make sure allare mated on(s) andre-check. on ofthe ons and ng the the ng ff

shuto page 29. per “Unitdraining andFilter Cleaning” OVER TIGHTENING. TIGHTEN ALLSCREWSTO PREVENT SCREWDRIVERS ORDRILLS,HAND NOTICE: DONOT USEELECTRIC working onornearany electrical parts. confirm that power isoff before Use anon-contact circuit tester to disconnect power to thewater heater. the water heater. You must physically remote doesNOT disconnect power to power button onthewater heater and the circuit breaker, asappropriate. The controller asidefor re-installa maintenance sheet. Set thebuilt-in diagram onpage 28orinthe computer board. Re the built-in controller from the computer board. Carefully disconnect Figure 72. 2 1 4 3 ff valve. water heater at themanualgas heater anddrain theheater as Shut o wall outlet orturningitoff at heater itfrom byunplugging the Disconnect power to thewater controller andfollow itto the Locate thewire onthebuilt-in Shut o ff ff thewater supplyto the thegas supplyto the ference thewiring on. See See on. MAINTENANCE

water to the water the water to water the gas supply to the supply to the gas ff ff Shut o Disconnect power to the water the water to power Disconnect the by unplugging it from heater at or turning it off outlet wall Shut o water heater at the manual gas the manual gas at heater water the system. and drain heater valve. ff WARNING! WARNING! necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. of others, read and follow each step step each and follow read of others, do to Failure of these instructions. injury or in personal so could result death. 3 1 2 the circuit breaker, as appropriate. The as appropriate. breaker, the circuit and heater on the water button power to power disconnect does NOT remote physically must You heater. the water heater. the water to power disconnect Removing Removing and the Replacing Piping Water System Components and the safety safety your ensure • To the skills do not have • If you the water and replacing Removing components: piping system Head Needed: #2 Phillip’s Tools Screwdriver USE ELECTRIC NOT DO NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TIGHTEN ALL SCREWS TO TIGHTENING. OVER shuto Cleaning” and Filter see Unit Draining under the on p. 29. Place a bucket

ff on and on ng the on of the on of theon te. Press the On/ te. Press mated all are sure ons. Make the to controller ach the built-in ows with a full stream. Let the Let with a full stream. ows ons by restoring water to the to water ons by restoring fl front of the water heater. heater. of the water front A back heater turn the water on to water heater. heater. water heater by plugging it into the by plugging it into heater secure with the four screws screws four with the secure shuto the manual gas at heater to check the wiring connec to check the piping heater, water and not pinched or under tension. and not pinched or under screw securing the thermistor. securing the thermistor. screw Reconnect power to the water the water to power Reconnect opera proper Verify Replace the front cover and cover the front Replace the water supply to on the gas Turn Before proceeding , take a moment , take proceeding Before the to power restoring Before Ensure all wires are routed correctly routed are all wires Ensure Remove the metal fastener or fastener metal the Remove On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 61 ce: keep the screw(s) or metal the screw(s) ce: keep l it bu 8 ff 9 6 7 13 14 11 12 10 correctly and seated securely. and seated correctly thermistors. pipe connec Allow a leaks. any and check for system pressurize. to the system for moments few Open a hot immediately. leaks any Correct run to allow the water and faucet water un water run full stream for three minutes three for run full stream water closing the faucet. before fasteners for re-installa for fasteners wall outlet or turning it on at the circuit the circuit or turning it on at outlet wall as appropria breaker, O on. removed earlier. Note the placement of the placement Note earlier. removed when se controller the built-in connec proper ensure to in place cover front alignment. valve. No Reconnect the wire from the built-in the built-in from the wire Reconnect See board. the computer to controller 72. Figure #408

rrrrrrrr oor to gure below. gure nec fi Thermistor Connector Con

Built In Controller Outlet Thermistor #408 Outlet Thermistor Outlet Exhaust Thermistor #718 Thermistor Exhaust Heat Exchanger Thermistor #411 Thermistor Exchanger Heat Thermistor locations. Thermistor Built-in controller removal. controller Built-in

replaced using the replaced Locate the thermistor(s) to be to the thermistor(s) Locate Return Thermistor #731 Thermistor Return 5 Inlet Thermistor #407 Inlet Thermistor Figure 73: Figure Figure 72: Figure MAINTENANCE 62 • On-Demand Water Heater Handbookfor Service X3PModels Figure 75: controller asidefor re-installa maintenance sheet. Set thebuilt-in diagram onpage 28orinthe computer board. Re the built-in controller from the computer board. Carefully disconnect installa front cover andscrews asidefor re- the cover to thewater heater. Set the port located onthebo water heater andopentheplas completely drain before proceeding. the water heater. Allowthesystem to 5 4 controller andfollow itto the Locate thewire onthebuilt-in to remove the4screws securing Use aPhillips-headscrewdriver

on. Standard Pipingconfiguration 409 450 458 462 (16-25A) ference thewiring (16-25A) om le 462 (16-25A) 458 462 on. sideof c drain JOINT C 468 483 456 (12.7) JOINT B 735 482 (16-25A) 462 Figure 74: immediately. nicks are present replace them 7 6 (12.7) 735 (16A) 458 461 456 490 726 458 Note thetypeofmetal fastener Inspect theo-ringswhenr when removing andreinstalling plas (12.7)

735 Built-in controller removal. 403 489 c piping joints, if any any if cpipingjoints, (16-24A) 488 458 456 Built InController (12.7) 735 462 481 402 404 456 ConnectorC o 456 nn 406 ec (16A) to 457 461 458 461 (16A) oor 458 JOINT G 487 486 JOINTF 461 (16A) r 458 405 (12.7) 456 735 eplacing eplacing

cuts or cuts or 735 (12.7) 456 JOINT E 485 (12.7) 735 controller to thecomputer board. Reconnect thewire from thebuilt-in for correct typeandplacement. them. Refer them. correctly andseated securely. pipe connec 456 9 8 (16A) 461 404 482 458 (16A) 461 406 Before proceeding ,take amoment A the front ofthewater heater. to checkthewiringconnec 458 ach thebuilt-in controller to 457 JOINT C (12.7) 735 483 405 ence Figure 75&Figure 76 ons. Make sure allare mated 456 484 on and MAINTENANCE

ff on of the ess the On/ te. Pr te. 735 (12.7) 735 (12.7) back heater turn the water on to heater by plugging it into the by plugging it into heater heater. water heater at the manual gas shuto gas the manual at heater Reconnect power to the water the water to power Reconnect opera proper Verify Turn on the gas supply to the water the supply to on the gas Turn 484 On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 63 bu ff 12 13 14 O on. wall outlet or turning it on at the circuit the circuit it on at or turning outlet wall as appropria breaker, valve. ng the 482 JOINT B 735 (12.7) Crossover Crossover configuration

ows with a full stream. Let the Let a full stream. with ows ons by restoring water to the to water ons by restoring fl secure with the four screws screws with the four secure water heater, check the piping check heater, water Replace the front cover and cover the front Replace Before restoring power to the to power restoring Before l it 11 10 Figure 76: Figure water run full stream for three minutes three for run full stream water closing the faucet. before system and check for any leaks. Allow a leaks. any and check for system pressurize. to system the for moments few a hot Open immediately. leaks any Correct run to and allow the water faucet water un front cover in place to ensure proper proper ensure to in place cover front alignment. removed earlier. Note the placement of the placement Note earlier. removed when se controller the built-in connec MAINTENANCE valve. OVER TIGHTENING. TIGHTEN ALLSCREWSTO PREVENT SCREWDRIVERS ORDRILLS,HAND NOTICE: DONOT USEELECTRIC Screwdriver Tools Needed:#2Phillip’s Head Removing therecirculation pump: • Ifyou donothave theskills • To ensure your safety andthe 64 • On-Demand Water Heater Handbookfor Service X3PModels parts. working onor near any electrical confirm that power isoff before Use anon-contact circuit tester to water heater. physically disconnect power to the power to thewater heater. You must and remote does NOT disconnect The power button onthewater heater at thecircuit breaker, asappropriate. Pump Recircula Replacing the Removing and 3 2 1 personal injuryordeath. Failure to dosocouldresult in each step oftheseinstructions. safety ofothers, read andfollow qualified service technician.qualified service proceed. Seekassistance from a procedure correctly, donot necessary to complete this WARNING! Use aPhillips-headscrewdriver to Shut o Disconnect power to thewater heater at themanualgas shuto remove the4screws securingthe the wall outlet orturningitoff heater itfrom byunplugging ff thegas supplyto thewater on ff

before proceeding. Allow thesystem to completely drain bo plas under thewater heater andopenthe See draining page 29.Placeabucket cover andscrews asidefor re-installa cover to thewater heater. Set thefront Figure 78: uses a16Ametal fastener, Connec Figure 77: See Figure 78. piping to therecircula Figure 77. controller asidefor re-installa maintenance sheet. Set thebuilt-in diagram onpage 28orinthe computer board. Reference thewiring the built-in controller from the computer board. Carefully disconnect 2 6 5 4 and om le om 2 c drain portlocated onthe Remove thethree metal Shut o Locate thewire onthebuilt-in heater anddrain thesystem. fasteners securingtheplas controller andfollow itto the

Metal Fastener andPipeJoint Re- Built-in controller removal. 3 1 use12.7Ametal fasteners. sideofthewater heater. ff water to thewater Joint “G” #487 Joint “E”#485 Built InController 3 “G ” #4 ConnectorC o nn o pump. on 487 ec to oor r on. See See on. ons ons on. 1 c moval. Figure 78. sec pump. See from thewater heater. SeeFigure 80. Figure 79: piping joints to therecircula Replacing therecirculation pump: Figure 80: base ofthewater heater. SeeFigure 79. screws removed earlier. SeeFigure 79. immediately. nicks are present replace them 12 11 10 1 6 9 8 7 usesa16Ametal fastener, ons asidefor re-installa Secure thenewrecircula Remove theplas Rea Reconnect plas Connect thewiringremoved Unplug thewiringto the “E” andJoint “G”. Set these earlier to thenewrecircula recircula fasteners securingtheplas to thewater heater withthetwo Inspect theO-rings,ifany cutsor Remove thetwo screws securing the recircula Pump ScrewsP

Pumpscrew removal. Recirculation pumpwiringconnector. um Figure 80. ach thethree metal p S S See crecrc on pump and remove it onpumpandremove it ws Figure 78. on pumpto the Wiring Connector c pipingjoints. c pipingJoint on pump. on pump on. See See on. on on c MAINTENANCE c 1 ons on. See rrrrrrrr oor to ec 487 on pump. nn o Connector C side of the water side of the water 33 port located c drain Built In Controller Joint “E” # 485 Joint Joint “G” # 487 # 4 “G” “G” Joint Joint water to the water the water to water ff om le use 12.7A metal fasteners. fasteners. use 12.7A metal 1 3 Built-in controller removal. controller Built-in Re- and Pipe Joint Fastener Metal

heater and drain the system. the system. and drain heater fasteners securing the plas fasteners controller and follow it to the to it and follow controller Shut o metal the three Remove Locate the wire on the built-in the built-in on wire the Locate 2 and 5 6 4 2 Place a bucket under the water heater heater under the water Place a bucket and open the plas on the bo completely to Allow the system heater. proceeding. before drain See Figure 82. See Figure Figure 82: Figure moval. Figure 81: Figure the recircula piping to Connec fastener, uses a 16A metal computer board. Carefully disconnect Carefully board. computer the from controller the built-in wiring the Reference board. computer the 28 or in on page diagram the built-in Set sheet. maintenance re-installa aside for controller Figure 81. Figure on. the gas supply to the supply to the gas ff remove the 4 screws securing the the 4 screws remove heater by unplugging it from the by unplugging it from heater at or turning it off outlet wall water heater at the manual gas the manual gas at heater water Shut o to Use a Phillips-head screwdriver Disconnect power to the water the water to power Disconnect valve. ff On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 65 WARNING! WARNING! necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. safety of others, read and follow and follow read of others, safety of these instructions. each step in so could result do to Failure injury or death. personal 2 3 1 cover to the water heater. Set the front the front Set heater. the water to cover re-installa aside for and screws cover the circuit breaker, as appropriate. The as appropriate. breaker, the circuit and heater on the water button power to power disconnect does NOT remote physically must You heater. the water heater. the water to power disconnect • To ensure your safety and the safety your ensure • To the skills do not have • If you Head Needed: #2 Phillip’s Tools Screwdriver USE ELECTRIC NOT DO NOTICE: OR DRILLS, HAND SCREWDRIVERS PREVENT TIGHTEN ALL SCREWS TO TIGHTENING. OVER Use a non-contact circuit tester to tester circuit Use a non-contact before is off power that confirm parts. electrical on or near any working Removing Removing and the Replacing and Port Drain Tube Drain shuto

ff ng the ons. Make on of the ess the On/ use 12.7A metal metal use 12.7A te. Pr te. 3 and 2 the Let with a full stream. ows fl ach the built-in controller to controller built-in ach the ons on to turn the water heater heater turn the water on to ons by restoring water to the to water ons by restoring on and pipe connec heater at the manual gas shuto the manual gas at heater heater by plugging it into the by plugging it into heater heater. water secure with the four screws screws with the four secure water heater, check the piping heater, water moment to check the wiring check the to moment the front of the water heater. heater. of the water the front l it l Verify proper opera proper Verify Turn on the gas supply to the water supply to on the gas Turn Reconnect power to the water the water to power Reconnect Replace the front cover and cover the front Replace Before restoring power to the to power restoring Before Before proceeding , take a , take proceeding Before A bu ff 19 18 17 16 15 14 13 sure all are mated correctly and seated correctly mated all are sure securely. Allow a leaks. any and check for system pressurize. to the system for moments few Open a immediately. leaks any Correct to and allow the water faucet hot water run un water run full stream for three minutes three for run full stream water closing the faucet. before fasteners. See Figure 78. See Figure fasteners. O wall outlet or turning it on at the circuit the circuit or turning it on at outlet wall as appropria breaker, removed earlier. Note the placement of the placement Note earlier. removed when se controller the built-in front cover in place to ensure proper proper ensure to in place cover front alignment. connec connec Connec back on. valve. Reconnect the wire from the built-in the built-in from the wire Reconnect See board. the computer to controller 77. Figure MAINTENANCE step 10. 66 • On-Demand Water Heater Handbookfor Service X3PModels Figure 85: Keep thefastener for re-installa primary heat exchanger outlet pipe. For replacing Drain Tube con For replacing Drain Port go to step 14. Figure 84: Figure 83: base ofthewater heater. SeeFigure 83. Figure 82. sec from thewater heater. SeeFigure 84. later. SeeFigure 85. 10 7 9 8 ons asidefor re-installa Copper DrainCo Tube Remove the6-15metal fastener Unplug thewiringto the Remove theplas ppp securing thedrain tubeto the recircula “E” andJoint “G”. Set these Remove thetwo screws securing the recircula

Upper connection point Recirculation pumpwiringconnector. Pumpscrew removal. Pump ScrewsP er Drain Tu um p S S crecrc on pumpandremove it ws be 6-15 Metal Fastener on pumpto the Wiring Connector c pipingJoint nue with on. See See on. on on Figure 86: Figure 87: water heater. SeeFigure 87. Keep thefastener for re-installa base ofthewater heater enclosure. Replacing thedrain port: them immediately. any cutsornicks are present replace removed earlier. InspecttheO-rings,if Keep thefastener for re-installa base ofthewater heater enclosure. Inspect theO-rings,ifany cutsornicks later. SeeFigure 86. later. SeeFigure 86. 15 14 13 12 11 16 Copper Drain Tube Drain PortScrew r Remove thescrew securingthe Remove the6-15metal fastener Install thenewcopper drain pipe Remove theolddrain tube. Remove the6-15metal fastener Install thenewdrain portusing drain portto thebo securing thedrain tubeto the using the6-15metal fasteners securing thedrain tubeto the the screw removed earlier. Drain

Lower connection point Drain portscrew. T u be e See Figures 95-96. 6-15 Metal6 Fastener -1 5 M et om ofthe on on on Figure 81. controller to thecomputer board. See Reconnect thewire from thebuilt-in are present replace themimmediately. them immediately. any cutsornicks are present replace removed earlier. InspecttheO-rings,if un water faucet andallowthewater to run Correct any leaks immediately. Openahot few moments for thesystem to pressurize. system andcheckfor any leaks. Allow a correctly andseated securely. connec pipe connec immediately. nicks are present replace them Connec fasteners. SeeFigure 82. before closingthefaucet. water runfullstream for three minutes See Figure 84. piping joints to therecircula screws removed earlier. SeeFigure 83. 20 19 18 17 24 23 22 21 1 usesa16Ametal fastener, l it l Secure therecircula Connect thewiringremoved Reconnect plas Reinstall thecopper drain pipe Before restoring power to the Before proceeding ,take amoment A Rea the front ofthewater heater. using the6-15metal fasteners Inspect theO-rings,ifany cutsor water heater, checkthepiping to checkthewiringconnec earlier to therecircula fasteners securingtheplas the water heater withthetwo fl ons byrestoring water to the ows withafullstream. Let the ons ach thebuilt-in controller to ach thethree metal ons. Make sure allare mated See Figures 82&83. 2 and 3 c pipingjoints. use12.7Ametal on pumpto on pump. pump. on on pump. on and c MAINTENANCE

ff on and on ng the on of the ess the On/ M4 Screw te. Pr te. mated all are sure ons. Make ach the built-in controller to controller the built-in ach Thermistor Inlet Plug Inlet Thermistor

back heater turn the water on to to check the wiring connec to screws four with the secure shuto the manual gas at heater the by plugging it into heater heater. water the front of the water heater. heater. of the water the front Before proceeding , take a moment , take proceeding Before and cover the front Replace the water to supply on the gas Turn the water to power Reconnect opera proper Verify A Closing Plug #732 bu ff 8 9 7 12 10 11 front cover in place to ensure proper proper ensure to in place cover front alignment. Figure 89: Figure pipe connec securely. and seated correctly of the placement Note earlier. removed when se controller the built-in the circuit or turning it on at outlet wall as appropria breaker, O on. Secure it in place with the M4 screw it in place Secure earlier. removed valve. Reconnect the wire from the built-in the built-in from the wire Reconnect See board. the computer to controller 88. Figure on. rrrrrrr ooor to ec ference the wiring ference nn o on. Connector C the gas supply to the supply to the gas Built In Controller ff Built-in controller removal. controller Built-in on.

Locate the wire on the built-in on the built-in the wire Locate the it to and follow controller this and keep 89. Remove Figure 89. in Figure plug referenced Shut o Use a Phillips-head screwdriver securing the 4 screws remove to Disconnect power to the water the water to power Disconnect the by unplugging it from heater at it off or turning outlet wall water heater at the manual gas the manual gas at heater water Locate the M4 screw as shown in the M4 screw Locate the closing and replace Remove valve. ff On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 67 5 6 4 2 3 1 computer board. Carefully disconnect disconnect Carefully board. computer the from controller the built-in Re board. computer 28 or in the on page diagram built-in the Set sheet. maintenance re-installa aside for controller re-installa for screw the cover to the water heater. Set the Set heater. the water to the cover re- aside for and screws cover front installa the circuit breaker, as appropriate. The as appropriate. breaker, the circuit and heater on the water button power to power disconnect NOT does remote physically must You heater. the water heater. the water to power disconnect Figure 88: Figure Use a non-contact circuit tester to to tester circuit Use a non-contact before is off power that confirm parts. electrical on or near any working shuto NOTICE: DO NOT USE ELECTRIC USE ELECTRIC DO NOT NOTICE: HAND OR DRILLS, SCREWDRIVERS PREVENT ALL SCREWS TO TIGHTEN TIGHTENING. OVER

ff ff ng the on of the ess the On/ te. Pr te.

back heater turn the water on to heater at the manual gas shuto the manual gas at heater heater by plugging it into the by plugging it into heater heater at the manual gas shuto the manual gas at heater heater. water secure with the four screws screws the four with secure Turn on the gas supply to the water to supply on the gas Turn opera proper Verify Reconnect power to the water the water to power Reconnect Turn on the gas supply to the water supply to on the gas Turn Replace the front cover and cover front the Replace

WARNING! WARNING! necessary to complete this complete necessary to do not correctly, procedure a from Seek assistance proceed. qualified service technician. bu safety of others, read and follow and follow read of others, safety of these instructions. each step in do so could result to Failure injury or death. personal ff 28 25 29 27 26 Plug Thermistor Inlet Inlet Thermistor Replacing the Replacing Removing Removing and wall outlet or turning it on at the circuit the circuit it on at or turning outlet wall as appropria breaker, removed earlier. Note the placement of the placement Note earlier. removed se when controller the built-in front cover in place to ensure proper proper ensure in place to cover front alignment. • If you do not have the skills the do not have • If you the thermistor and replacing Removing plug:inlet Head Needed: #2 Phillip’s Tools and needle nose pliers. Screwdriver • To ensure your safety and the safety your ensure • To O valve. on. valve. COMPONENTS CMOET DIAGRAMS COMPONENT 68 • On-Demand Water Heater Handbookfor Service X3PModels 056

Case assembly Built-in controller 002

050

053

722

007

050 003

723

006

052

008

703

704

140 Surge boxassembly

053

702

005

001

706

004

052

727 052

714

705

COMPONENTS

715 715

701 Y: YELLOW 715 controller Remote Built-in controller Sensor Pressure Increase button Increase MAX button button Decrease DIP switches MIN button thermistor Return thermistor Heat exchanger Heat Outlet thermistor Inlet thermistor

BK BL WW Exhaust thermistor Exhaust

W R 715

W

6 6 78 612345 78 2345 1 12345 R

O: ORANGE BR: BROWN BL: BLUE ON ON ON Flow 715 Sensor

722 BKBK BK BK BK BK BK BK 715 W W BK BK R R 715 BK G: GREEN R: RED P: PURPLE

715 BK 715 W Parent 715 W BK W R 715 BK Ground BK

W: WHITE BK: BLACK LB: LIGHT BLUE Easy-Link ༃༄ W 715

715 rod 715 Flame R G Y 709 Y 715 toring BL G

120 VAC Moni BK 709 W 714 BL G Y 715 O

eless G r W BK R G Wi 708 BR Ground

SW BK 715 714 708 W R W BK P P BK 9 BK Ground 53 73

W box Surge 715 P P 708 Y 737 R BL BK BK Y 738 W BR R 103 IG

715 715 On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 69 O Y Heater Heater Heater Heater Y Y W Y Y R R Y Flow W Valve Y Adjust O BL

R R BL O W BR rod BL Igniter 103 W BR Y Y

G R Y LB BR s

BL 708 s a BK 738 p BL BL W Y Y y Valve FM O B Pump Y G R R BK BK BL LB

716 BL BL BL BL BK BK BL BR BR 721 Heater 131 SV1 SV3 MV SV2 Hi- limit Heater O.H.C.F Thermostat Thermostat

Air damper

Computer board assembly board Computer COMPONENTS 70 • On-Demand Water Heater Handbookfor Service X3PModels 104 Gas line 152 066 119 153 152 153 117 055 a inlet Gas B 462 131 057 B 066 118 057 116 102 135 067 069 130 unrassembly Burner 136 129 122 145 123 a oo assembly motor Fan 139 455 127 A A 124 138 125 132 113 112 138 101 115 126 132 133 134 103 COMPONENTS

423

416

136

470

471 707

E 718 434 464

067 709

058

136 433

454 109 009

412 052 068

108 Hi-limit switch Hi-limit

141 710 063

721 111

708 107 assembly

737

067 053 Exhaust duct Exhaust

422 710

711

413

432 431 418

465

420 455

463 463

052 474

456 D D

C 472

452

462

455 420 Heat exchangers Heat

458 401 On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 71 469 411

064

462

067

421

454

456 C 474

459 458

E 467 468 F 458 453 473 415

419

462

G 064

466 415

453

414

415

462 458

453

451 407

454 459 Water way 1 Water COMPONENTS 72 • On-Demand Water Heater Handbookfor Service X3PModels 462 726 409 458 451 736 Water way2 052 up&rtr inlet return & Pump 056 052 414 ae outlet Water 461 404 456 417 458 450

J 406 454 462 059 457 735 408 483 F 487 458 405 481 461 417 454 462 059 458 K 461 458 731 458 404 ae inlet Water 052 I 406 483 457 K 735 G 405 462 490 735 454 732 458 456 456 489 484 059 417 C c SCM 735 140 462 yasvalve Bypass 739 458 456 H 488 H 456 482 461 ŽŶŶĞĐƟŽŶ I J 458 458 461 486 461 735 402 735 458 735 456 456 485 456 403 735 456 482 COMPONENTS No.123 sensor Pressure 124 Tube Inlet Air 125 P40 EPDM O-ring 126 Description body Venturi 127 ring NBR Oval 129 gasket Orifice 130 assembly solenoid valve Gas 131 wire solenoid valve Gas 132 # Part 100320320 P50 FKM O-ring 133 duct Venturi 134 100320379 N/A O-ring P75 FKM135 100320383 M3x18 FEZN screw Pan 136 100320380 M4x12 screw Pan 100320381 138 M4x12 SUS2 screw Tapping 100320382 139 N/A M3x8 screw tight Tapping 140 SUS3 M4×12 (Coated) screw Truss 141 100320384 M4x10 screw Pan 145 Orifice NA145 100320385 100320386 N/A Orifice LP152 N/A O-ring P16 NBR153 N/A O-ring P22 NBR N/A 401 N/A assembly exchanger Primary heat 402 sensor valve/Flow Flow adjustment 403 valve Bypass 404 inlet Water N/A 405 100320388 plug filter Inlet 406 100320486 100320387 filter water Inlet 407 100320422 thermistor Inlet 100320420 408 100320423 thermistor Outlet 409 outlet Water 411 thermistor exchanger Heat 412 Hi-Limit switch413 100320466 fuse Overheat-cut-off 414 100320526 100074381 Block heater415 100074382 Block heater416 100320523 tube Drain 417 100320522 100320524 heater Inlet 418 assembly exchanger heat Secondary 419 100320527 fixing plate exchanger heat Large 420 100074334 100320390 gasket exchanger Heat 421 L fixing plate exchanger Small heat 100320391 100074684 100074683 N/A N/A N/A 100320392 N/A On-Demand Water Heater Service Handbook for X3P Models • X3P Models • Service Handbook for Heater On-Demand Water 73

001 Case assembly002 cover Front 003 port assembly Intake/Exhaust 004 Bracket005 bracket Top 006 Hose clamp007 tray Rain protection 008 100320352 plate Rain protection 009 port drain Condensate 050 N/A SUS410 M4×12 (W/Washer) screw Truss 052 100320351 SUS3 M4×10 (Coated) screw Truss 053 M4x10 SUS screw Truss 055 N/A FEZN M4x8 head screw Hex 056 100320353 M4x20 SUS410 screw Pan 057 N/A N/A M4x12 FEZN screw tight Tap 100074203 N/A 058 N/A N/A head Pan M3x6 SUS3 screw Tapping 059 head Truss M4x6 SUS3 screw Tapping 063 clamp 60 Wire 064 N/A N/A M4x10 Screw 066 N/A M4x10 screw Pan N/A 067 N/A N/A SUS M4x14 S coated screw Truss 068 M4x10 S screw tapping Truss 069 M4x12 MFZN sems screw Pan 101 knit burner Metal 102 assembly Gas valve 103 N/A 100074233 motor Fan 104 Gas pipe106 N/A N/A N/A N/A 107 N/A holder gasket Rod 108 Flame Sensor109 assembly rod Igniter 100320354 110 100320355 N/A111 cap Rod 112 Mixing chamber assembly113 100320356 Mixing chamber gasket115 Burner gasket 100320358 100320357 116 A Gas connection 100320360 100320359 N/A 100320372 100320373 N/A N/A 100320374 100320375 117 B Gas connection 118 Gas inlet 119 ring Gas inlet 122 Air damper assembly 100320376 100320319 100320378 100320377

No. Description # Part COMPONENT DIAGRAMS/ITEM NUMBERS DIAGRAMS/ITEM COMPONENT COMPONENTS COMPONENT DIAGRAMS/ITEM NUMBERS 74 • On-Demand Water Heater Handbookfor Service X3PModels 8 rs on 100320412 100314460 100320408 100320411 100320413 100320405 3way connection -Bypass, heat exchanger 100320409 490 SCMmanifold assembly 489 Brass joint 100320407 100320410 100320406 488 Joint G-Pumpinlet elbow 487 100320403 Joint F-3way connection withSCM,return 100320404 486 Joint E-Pumpoutlet straight 100320401 100074692 485 Joint D N/A484 Joint C-Tee Mixingandinlet 483 100320402 Joint B-Elbowpumpoutlet 482 Inlet pipe 100320397 481 Headerconnection gasket N/A 100320400 474 Headerconnection N/A 100320399 473 Headerconnection w/drain port N/A 100320398 472 O-ringP10FKM 471 Thermistor fixingplate 470 Drain port 100074297 469 P-heat exchanger outpipe 100074389 468 P-heat 100074410 exchanger inpipe 467 S-heat exchanger inpipe 100074282 466 Drain pipe 100076308 465 Flat heater 100076307 464 Drain pipe 100076306 100076305 465 Flat heater 100076303 464 Fastener “6-15” 463 N/A Fastener “16-25A” N/A 462 Fastener “16A” 461 Fastener “4-11” 100320396 459 O-ringP16FKM 100074310 458 O-ringP15FKM 100320395 457 O-ringP14FKM 100320394 N/A 456 O-ringP6FKM 455 O-ringP4FKM N/A 100320393 454 Heater fixingplate 453 Fusefixingplate Part # 452 Heater fixingplate 16 451 Outlet pipe 450 Exhaust portcap N/A 434 O-ringP60FKM 433 Exhaust ductgasket Description 432 Exhaust duct 431 Hoseclamp15 423 Smallheat exchanger fixingplate R 422 No. 3 3 atig 100314491 N/A N/A N/A 100076400 100276683 100276681 N/A X3™Cartridge 100320419 739 Recirculation 100320418 pumpwire 738 Igniter cord 100276680 737 Pumpfixingplate N/A 736 Fastener "12.7" 735 100320417 100320416 Closingplug N/A N/A732 Return thermistor 731 Wall mounting bracket N/A 727 Recirculation pump 726 Fixingplate N/A 100320415 723 Built-in controller 722 Hi-limitswitch wire 721 Exhaust thermistor 718 Computer board cover N/A 716 24Vcables 100074601 N/A 100076100 715 120Vcables 714 Igniter fixingplate 100074326 711 Igniter assembly 100076470 100320414 710 Flamerod wire 709 Wiringfor Gasvalve, Hi-limit,OHCF, Igniter 708 Flat heater extension wire 100320427 Part # 707 120VAC Power ON-OFFswitch 100320426 706 Surge box fixingplate 100320425 705 120VAC wire 704 Surge box 703 Rubbergrommet Description 702 Computer board 199X3P 701 Computer board 180X3P 701 Computer board 160X3P 701 No. CONT. NOTES