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SATS CyberTWO Series 6-30 Ton “VFS” Vertical Floor Mounted Precision Control Air Conditioners

Product Guide Specification

*************************************************************************************************************** This section must be carefully reviewed and edited by the Engineer to meet the requirements of the specific project. Coordinate with other specification sections and the drawings as necessary. ***************************************************************************************************************

1.0 GENERAL

1.1 Summary

This specification describes requirements for a precision environmental control system. The CyberTWO “VFS” vertical floor-mounted air conditioning system shall provide precision temperature and/or humidity control for computer rooms or rooms containing telecommunications or other highly-sensitive heat load equipment where continuous 24 hour a day, 365 days a year air conditioning is required. Designed for front-only access, “CyberTWO” systems require minimum floor space. The units are designed with a wide range of options to handle both precision and comfort cooling applications.

The supplied system shall be labeled in accordance to UL 1995 Standard, and MEA NYC approved (MEA-163-88-E) listings. The system shall also be MET-c recognized by the Standards Council of Canada and provincial authorities throughout Canada.

The system model number shall be ______.

1.2 DESIGN REQUIREMENTS

The environmental control system shall be an SATS CyberTWO factory-assembled unit. The unit shall be designed for corner installation, requiring front only access through a hinged and removable front access panel. No allowance for side service access shall be required, however removable side access panels shall be provided for additional access. The CyberTWO Series units are especially adapted to raised floors and are available in both down-flow and up-flow air pattern configurations. On direct expansion models, the refrigeration system shall be split with a matching outdoor air-cooled condenser.

The evaporator section shall be specifically designed for high sensible heat ratio. The heat exchanger shall be propeller fan (for outdoor installation). Each system shall be capable of handling ______CFM (CMH) at ______inches (mm) of water external static pressure with (down discharge top return air flow, up discharge front return air flow, up discharge rear return air flow pattern. The unit shall have the cooling capacity of ______Btu/hr (kW) and the sensible cooling capacity of ______Btu/hr (kW), based on entering air condition of ______°F (°C) dry bulb and ______°F (°C) wet bulb. The humidifier shall have the capacity of ______lb/hr (kg/hr.). Reheat shall have a capacity of ______Btu/hr (kW). The main fan motor(s) shall be ______HP (kW).

The unit shall have a power supply of ______volts, ______phase, ______Hz.

1572 Tilco Drive  Frederick, Maryland 21704 USA Phone: 301-620-2033  Fax: 301-662-5487  www.stulz-ats.com

QG-VFS0042 Rev - Page 1 of 15 1.3 SUBMITTALS

A submittal shall be provided with the proposal and shall include: Single-line Diagram Dimensional, electrical, and capacity data; and Piping and electrical connection drawings.

1.4 QUALITY ASSURANCE

CyberTWO systems are designed and built using only quality components. Every unit passes through 10 quality assurance inspection stations. Each person involved with the welding, assembly, piping, wiring, testing, and final cleanup and crating initials their work. After final cleanup, the units are again inspected by our quality supervisor to ensure that the system received is in top condition. Each system is subject to a complete operational and functional test procedure at the factory.

2.0 PRODUCT

2.1 Standard Features/All Systems The system shall be a floor mounted precision air conditioner designed and built to the highest of industry standards. The system shall be complete and factory run-tested before shipment. The system shall be MET Laboratory (an NRTL) listed and MET-c recognized and labeled in compliance with UL 1995 (# SATS-1995). The system shall be MEA NYC (MEA-163-88-E) and Chicago Code approved.

2.1.1 Cabinet and Frame Construction

The cabinet and access panels shall be fabricated from 16 gauge galvannealed steel and powder-coat paint processed for décor matching and corrosion protection. The panels shall be lined with 2 lb/ft², high-density sound and thermal insulation and sealed with self-extinguishing gasketing conforming to NFPA 90A and 90B.

2.1.2 Electric System

2.1.2.1 Modular Motor Controllers

The systems shall incorporate modular motor controllers utilizing motor start protectors and circuit breakers to eliminate the need for fuses. All wiring shall be in accordance with the National Electric Code (NEC) and shall include:

* Motor branch circuit short circuit protection; * Motor load switching controllers (contactors) and * Motor overload protection.

The control circuit shall be a 24 VAC Class II low voltage circuit, including a circuit breaker for protection. Low voltage, high voltage, and common wires shall be color-coded and shall be individually numbered at each end for ease of service tracing. All wiring shall be in accordance with the National Electric Code (NEC).

QG-VFS0042 Rev - Page 2 of 15 2.1.2.2 Remote Stop / Start Contacts

Included in the system’s electrical control circuit shall be a 2 –pin terminal connection for remote stop/start of the CyberTWO air conditioner by remote source.

2.1.2.3 Main Power-Electric Non-Fused Disconnect Switch

The unit mounted main power disconnect switch factory provided, is as standard. The disconnect switch shall be dust-proof, non-fused type with a lockable handle.

2.1.3 Direct Expansion System

2.1.3.1 A-Frame Coils

The system shall be configured for a draw-thru air pattern to provide uniform air distribution over the coil face. The coils shall be an A-Frame design to provide maximum coil surface area and minimum depth to provide a high sensible cooling capacity. The coils shall be seamless drawn copper tubes, mechanically bonded to tempered aluminum fins with a dual interlaced circuiting design for maximum heat transfer. Coil end plates shall be hot dipped galvanized steel. The evaporator coil shall be mounted in an insulated stainless steel condensate drain.

The evaporator coil shall have a ______ft² (m²) face area and be ______rows deep. It shall be constructed of copper tubes and aluminum fins and have a maximum face velocity of ______ft/min (m/s) at ______CFM (CMH). Refrigerant flow shall be controlled by externally equalized thermostatic expansion valves.

2.1.3.2 Refrigeration System

All refrigerant piping shall be refrigerant grade tubing. Each refrigeration circuit shall include, as a minimum a refrigerant drier/strainer sight glass with moisture detector, a thermal expansion valve with rapid bleed port feature and external equalizer, an evaporator coil, a compressor, a high pressure switch with manual reset, and a low pressure switch with automatic reset.

Split/Remote systems shall have a liquid line solenoid for refrigerant isolation to prevent liquid slugging. All high-pressure joints shall be brazed, and the entire system shall be pressure tested at the factory with dry nitrogen, evacuated to at least 50 microns and fully charged with refrigerant.

2.1.3.3 Dual Scroll Compressors

DX systems shall be provided with two independently circuited, high efficiency, high reliability, and low noise scroll compressors. Each compressor shall be complete with rotolock service valves, charging and service shraeder ports, internal vibration isolation, internal thermal overloads, an internal pressure relief valve, an internal discharge gas vibration eliminator, and external vibration mounting isolation.

2.2 Chilled Water System Components

2.2.1 Chilled Water Cooling Coil

QG-VFS0042 Rev - Page 3 of 15 The chilled water coil shall be an A-Frame design to provide maximum coil surface area and minimum depth to provide a high sensible cooling capacity. The coils shall be seamless drawn copper tubes, mechanically bonded to tempered aluminum fins for maximum heat transfer. Coil end plates shall be hot dipped galvanized steel. The evaporator coil shall be mounted in an insulated stainless steel condensate drain.

The cooling coil shall have a ______ft2 (m2) face area and be 3 rows deep. The coil shall be designed for less than 500 ft/min face velocity. The water circuit shall be designed to distribute water into the entire coil face area. The coil shall be supplied with _____°F (°C) entering water temperature with a ______°F (°C) rise. The coil shall be supplied with ______gpm (l/s) of chilled water and pressure drop shall not exceed ______psi (kpa).

2.2.2 Chilled Water Control

A factory installed 3-way modulating valve rated for a maximum 400 psig w.w.p. shall automatically meter the flow of water to the chilled water coil.

2.3 Blowers / Motors

2.3.1 Belt Driven Systems

The blower(s) shall be belt driven with a double-width, double-inlet housing and forward-curved blades and permanently lubricated ball bearings sized for a minimum life span of 100,000 hours of service life (L10 Life). The blower(s) shall be dynamically and statically balanced to minimize vibration and operate in the Class 1 operating range. The blower(s) shall be corrosion protected with a painted housing and impeller wheel. The blower(s) shall be belt driven with dual belts sized for 200% of the fan motor horsepower. The blower shall have an adjustable base for belt tensioning and a locking system to prevent the motors from moving. The motor’s drive sheaves shall have an adjustable pitch to change the speed of the blowers. The motor shall be 1725 rpm and shall have overload protection and a minimum NEMA service factor of 1.15.

The fan motor shall be ______hp (kW) at 1750 rpm.

2.3.2 Direct Driven EC-Radial Fan Systems

The blower(s) shall be direct driven, single inlet, two-fold backward curved radial fan with an electronically commutated motor for maintenance free operation. The motor shall include: integrated electronic control board and direct microprocessor control signaling for fan speed control, soft-starting capabilities, RS-485 BUS connection, and integrated current limitations. Each fan shall be low noise, low vibration manufactured with an anti-corrosive aluminum impeller. Each fan impeller shall be dynamically and statically balanced in two planes to minimize vibration during operation.

2.4.1 Microprocessor Temperature & Humidity Controller with Alarms – C6000

The floor mounted A/C shall be provided with SATS' C6000 Microprocessor based Temperature and Humidity controller with Alarms. The controller shall incorporate a "user-friendly", menu driven, operating environment, to allow easy system setup and operation.

QG-VFS0042 Rev - Page 4 of 15 The C6000 is a complete microprocessor based control system designed for operating, controlling and monitoring the CyberTwo precision air conditioning unit.

The C6000 controller shall include a full-featured LCD, Graphical display for visual indication of the units operating conditions.

2.4.1.2 User Interface

The User Interface shall feature an easy to read, liquid-crystal alpha-numerical display. The attractive unit mounted interface, allows the operator to visually monitor and customize unit functions and settings. The controller is operated via a 4-key menu-driven windows type structure, in three different modes; Information, Operation, and Service.

2.4.1.3 Field Configurable

The C6000 controller is field program configurable and capable of matching the unique needs of any data center, telecommunication or other critical area.

2.4.1.4 Sensor Location Options

As a standard, the C6000 temperature and humidity sensor shall be factory unit mounted in the return air stream of the Precision AC unit, after the filter(s).

2.4.1.5 System Setup & Adjustments

The C6000 shall be completely factory preprogrammed, and therefore, most applications will require no field setup. However, the “default” set points and their ranges are easily adjusted from C6000 interface.

2.4.1.6 Unit Status Display

The C6000 LCD Graphic Display shall indicate current room status:

• Current Dry Bulb Temp Set Point • Current Relative Humidity Set Point • Actual Time

2.4.1.7 Current Unit Status

The C6000 LCD Graphic Display shall indicate current unit functions via symbol identification:

• Cooling • Heating • Humidifying • Dehumidifying • Reheating

The C6000 shall provide graphical display of room temperature and humidity for the last 24 hours of operation.

QG-VFS0042 Rev - Page 5 of 15 2.4.1.8 Run Times

The historical run-time in hours of the following major components shall be available directly from the C6000 interface: (if applicable)

• Evaporator Blower Motor • Compressor • Humidifier • Chilled Water Valve • Free-Cooling Valve • Alternate Water Source Valve

2.4.1.9 Alarm Conditions

Alarm conditions activate an audible and visual indicator. An alarm shall be acknowledged through a button located on the user interface.

The C6000 alerts to the following alarm conditions (if applicable):

• High Temperature • Dirty Filter • Low Temperature • Smoke Detection • High Humidity • Firestat • Low Humidity • Leak Detection • High Head Press • GC Pump Failure • Low Suction Press • Sensor Failure • Loss of Air Flow • Comm. Failure

2.4.1.10 Summary Alarm Contact

A summary alarm dry-contact (n/o) connection shall be available for remote annunciation of an alarm condition. An additional user-defined Custom alarm dry-contact shall also be available on most system configurations.

2.4.1.11 Alarm History

The C6000 controller provides users with a recorded history of the last 80 alarms, including the time and date of the alarm.

2.4.1.12 Control Inputs/Outputs

The C6000 is capable of both digital (on/off) and analog input and output device control. Prior to shipment, each Precision AC unit's C6000 is factory program configured to match the unit's system operational requirements.

2.4.1.13.1 Digital (on/off) and Analog (0-10 VDC) Inputs & Outputs

The C6000 I/O Board provides as a standard 10 digital outputs, 8 digital inputs, 7 analog inputs, and 4 analog outputs.

QG-VFS0042 Rev - Page 6 of 15 An expansion board shall increase the capability by providing and additional 8 digital inputs and 8 digital outputs.

2.4.1.14 Temperature Anticipation

The C6000 shall incorporate a self-calibrating and self-adjusting control logic that adjusts the response of the SATS air conditioner to changes in temperature and humidity. The system shall provide premium setpoint accuracy while controlling the room conditions rate of change, minimizing the equipment energy consumption and maximizing the system’s operating life and reliability.

2.4.1.15 Power Loss Restart

In the event of a loss of power to the system, the C6000 can be configured for Automatic or Manual Restart. The C6000's non-volatile memory enables the system to restart when power is restored, without the loss of the "last" stored set points and other system configuration settings.

2.4.1.16.1 Sequential Load Activation

To minimize the total in rush current loads during system startup/restart, the C6000 controller shall be configured for time-delay sequence startup. The user can designate specific unit restart time-delays, as well as, each unit's respective compressor, electric heater and/or humidifier. Unit restart delay can be adjusted from 0 to 10 minutes. Unit compressor, electric heater and/or humidifier restart delay can be adjusted from 0 to 60 seconds.

2.4.1.16.2 Recovery Delay

After a power loss, the C6000's Recovery Delay feature allows the Precision AC A/C to operate without initiating any high or low temperature or humidity alarms for a delayed period. This feature allows the A/C time (15 to 60 minutes adj.) to "pull-down" the conditioned space's load without nuisance alarms during initial startup or power loss restart.

2.4.1.17 Compressor Operations

2.4.1.17.1 Short Cycle Protection

Each compressor shall be protected from frequent compressor cycling through the C6000's minimum compressor ON and minimum compressor OFF short cycle timers.

2.4.1.17.2 Cold Start Time Delay

Each compressor of a DX Split system shall be protected from liquid slugging through the C6000's Cold Start compressor time delay. The Cold Start timer delays, and therefore, overrides the system's refrigerant low suction pressure switch during system startup. This allows the system time to build sufficient discharge pressure during cold weather startup.

2.4.1.18 Security

Multiple security levels prevent unauthorized adjustment of critical system parameters. The user may select a four-digit password for setpoint and configuration changes.

QG-VFS0042 Rev - Page 7 of 15 2.4.1.18.1 Keypad Lockout

The C6000 includes a selectable Keypad Lock-Out feature that prevents unauthorized users from making changes to system setpoints and settings available directly from the multi-function interface. Keypad Lock-Out eliminates the need for stat-guards.

2.4.1.19 Diagnostic & Service Mode

The C6000 shall incorporate a unique self-diagnostics algorithm that continually tests systems functions and hardware operation. In the event of such a failure, the user will be alerted to the condition via a visual and audible alarm.

2.4.1.19.1 Control Board

The Control Board shall initiate a self-test of the control system.

2.4.1.19.2 Input Diagnostics

All system inputs and output devices shall be continuously monitored for proper operation.

2.4.1.20 Night Set-back

The C6000 shall include Night Set-Back occupied/non-occupied energy saving modes. This feature enables the user to customize each unit's daily 5-day/weekly and 2-day/weekend operational scheduled.

2.4.1.21 Remote BMS Connection (MIB Gateway)

C6000 Inputs & Outputs shall be remotely monitored (address readable) and remotely controlled (address writable) via an Automated Logic Controls building management system (BMS) / local area network (LAN) control system that can communicate via a ModBus protocol. Each C6000 configured for BMS communication shall incorporate an RS-485 Serial Communication Port that is field connected to a factory provided wall mounted ModBus Gateway. Up to 32 precision AC units can be connected to a single MIB Gateway.

2.4.1.22 Supervisor Controller (Optional)

The precision AC system shall be provided with an optional C6000 Supervisor controller. The supervisor controller shall continually monitor the data transmission of the primary C6000 microprocessor I/O board and assume control if data transmission is interrupted. All previously adjusted setpoints and parameters of the primary controller are automatically transferred to the supervisor expect for the CPU address (required for remote BMS operation only).

2.5.1.23.1 Remote BMS Connection (ModBus Gateway)

C-6000 Inputs & Outputs shall be remotely monitored (address readable) and remotely controlled (address writable) via any building management system (BMS) / local area network (LAN) control system that can communicate via a ModBus protocol. Each C-6000 configured for BMS

QG-VFS0042 Rev - Page 8 of 15 communication shall incorporate an RS-485 Serial Communication Port that is field connected to a factory provided wall mounted ModBus Gateway. The units of a CyberLAN ModBus Group must be connected to each other and then to the ModBus Gateway via sheilded serial twisted- pair cabling. This cabling is not included in SATS' CyberLAN Remote Communications / ModBus Gateway option, as a standard. This cabling is typically provided by the installing contractor. A list of the addressable I/Os are available upon request from your local SATS Sales Representative.

2.5.1.23.2 16 Units Per CyberLAN ModBus

Each ModBus Gateway shall accommodate up to 31 (Thirty-One) A/C units in a group.

The units of a respective ModBus Gateway Group are daisy-chained together with one of the units connected directly to the ModBus Gateway. The total number of Gateways required for a given application will depend not only on the number of maximum (31) units each Gateway can accommodate, but also the space layout.

2.6. Humidity Control

2.6.1 Canister Steam Humidification

The humidifier shall be an electrode steam canister type and shall have an adjustable humidity output setting from 25 to 100% of the full rated humidifier capacity. The humidifier shall have an automatic flush cycle that senses the current consumption of the humidifier and controls mineral concentration of the water. A "Change Cylinder" light shall notify service personnel when the humidification output is below rated requirements and when maintenance is due.

2.7 Dehumidification Cycle

The floor A/C shall provide refrigeration-based dehumidification mode. Moisture is condensed on the cooling coil and discharged through the condensate drain. Reheat (electric, hot gas, steam, or hot water) shall be provided to offset sensible cooling during the dehumidification cycle.

2.7.1 Two-Stage Electric Heat/Reheat: (standard)

A factory mounted and wired low-watt density, plated fin-tubular design electric resistance heater shall be included to provide automatic sensible re-heating as required during the dehumidification cycle and automatic heating mode. Electric heaters shall be provided with miniature thermal/magnetic circuit breakers, which shall protect each ungrounded conductor. Also included will be one automatic reset and one manual reset over-temperature safety device (pilot duty). Two (2) stages of electric reheat/heat shall be provided as standard.

2.8 Evaporator Air Patterns and Filtration: (select one)

2.8.1 Down-Flow: (standard)

The air conditioner shall be configured for a down-flow air pattern with free evaporator return air to the top and conditioned supply air discharge through bottom of the A/C into the raised floor.

QG-VFS0042 Rev - Page 9 of 15 The A/C shall have slide out, 4" deep, Class 2 (per U.L. Standard 900) filters. The filters shall be easily accessed through a front access door. The filters shall have an efficiency rating of at least, 30% dust-spot as measured by ASHRAE Standard 52-76 test method.

2.8.2 Up-Flow: (optional)

The air conditioner shall be configured for an up-flow air pattern with free evaporator return air through front filtered grille and conditioned supply air through the top of the unit.

Top "Ducted" Discharge with: * Front "Free" Return; * Rear "Ducted" Return; (A 1.0" Flanged duct connection shall be provided as a standard).

The A/C shall have slide out, 4" deep, Class 2 (per U.L. Standard 900) filters. The filters shall be easily accessed through a front access door. The filters shall have an efficiency rating of at least, 30% dust-spot as measured by ASHRAE Standard 52-76 test method.

2.8.3 Top Discharge Through two or three-way Grille Plenum Box with:

* Front "Free" Return; * Rear "Ducted" Return;

2.9 Standard Features / Individual Systems

2.9.1 Remote Outdoor Air Cooled Condenser

A remote outdoor, air cooled condenser, with direct driven propeller fan(s) shall be provided. The condenser shall be suitable for outdoor installation. Each fan shall be provided with a low RPM, outdoor rated, non-overloading direct driven motor. Each evaporator refrigerant circuit shall be directly connected to an independent condenser coil circuit rated for the full heat of rejection of the air conditioner at a 95°F ambient temperature. The following head pressure control features are offered:

* SCS-( )-DSA (096 to 683): Low Ambient Head Pressure Control down to a minimum ambient temperature of -20°F via variable fan speed head pressure control.

* SCS-( )-DAA (096 to 683): Low ambient head pressure control down to a minimum ambient temperature of -30°F via flooded head pressure control.

2.10 Remote Indoor Air Cooled Condenser

Centrifugal Fan - Vertical Floor Mount Configuration – Flooded Head Pressure Control

2.10.1 Fan Section

The HES-( )-DVCA shall be a vertical centrifugal fan type indoor condenser. The condenser shall be designed for indoor installation. The condenser cabinet shall be fabricated of mill galvanized steel. Fan sections shall have hinged doors with

QG-VFS0042 Rev - Page 10 of 15 latches. The fan shall be statically and dynamically balanced and designed to operate in a Class II environment. The fan shall be a double width, double inlet. Fan bearings shall be ball bearing type selected for 200,000 hour average life. The condenser shall have extended lube lines to the outside casing of the cabinet. The fan drive shall be a fixed drive at a 120% safety factor of the motor HP.

2.10.2 Coil Section

The condenser coil shall be designed with two independent refrigeration circuits. The coil shall have copper tubes and aluminum fins with heavy gauge casing of mill galvanized steel. The coils shall be designed with a corrugated fin design to provide optimum performance and strength.

2.10.3 Filter Section (Optional)

The condenser coil shall be designed with a High-Capacity filter box. The filter box shall include 2” deep, pleated type, 30% Average Efficiency filters. Filters shall be accessible from a side access door.

2.11 Water Cooled Systems

2.11.1 Integral Coaxial Tube-In-Tube Water Cooled Condensers (Model VFS-072/120-DW)

Each evaporator refrigerant circuit shall be provided with a factory installed single pass, counterflow configured, tube-in-tube coaxial condenser; designed and tested for a 450 psig. w.w.p.

The unit shall have a total heat of rejection of ______Btu/hr (kW), require ______gpm (l/s) of ______°F (°C) water, and have a maximum pressure drop of ______ft. (kpa.)

2.11.2 Stainless Steel Brazed–Plated Water Cooled Condensers (Model VFS-180/312-DW)

Each evaporator refrigerant circuit shall be provided with a factory installed single pass, counterflow configured, brazed plate heat exchanger, with integral subcooler, constructed of type 316 stainless steel; designed and tested for a 450 psig. w.w.p.

2.11.3 Head Pressure Control

Each refrigerant circuit’s head pressure shall be controlled by a factory-installed two-way water- regulating valve rated for 150 psig. w.w.p.

2.12 Glycol Cooled Systems

2.12.1 Integral Coaxial Tube-In-Tube Glycol Cooled Condensers (Model VFS-

072/120-DG)

Each evaporator refrigerant circuit shall be provided with a factory installed single pass, counterflow configured, tube-in-tube coaxial condenser; designed and tested for a 450 psig. w.w.p.

QG-VFS0042 Rev - Page 11 of 15 The unit shall have a total heat of rejection of ______Btu/hr (kW), require ______gpm (l/s) of ______°F (°C) water, and have a maximum pressure drop of ______ft. (kpa.)

2.12.2 Stainless Steel Brazed–Plated Glycol Cooled Condensers (Model VFS-180/312-DG)

Each evaporator refrigerant circuit shall be provided with a factory installed single pass, counterflow configured, brazed plate heat exchanger, with integral subcooler, constructed of type 316 stainless steel; designed and tested for a 450 psig. w.w.p.

2.12.3 Head Pressure Control

Each refrigerant circuit’s head pressure shall be controlled by a factory-installed two-way glycol regulating valve rated for 150 psig. w.w.p.

2.13 Optional Equipment / All Systems

2.13.1 Hot Gas Reheat

A factory piped and wired hot gas reheat valve shall be provided to divert the hot compressor discharge gas from the condenser to the hot gas reheat coil during the dehumidification cycle. This energy saving feature shall require no additional energy and is able to offset the sensible cooling capacity of the system while in the dehumidification mode.

2.13.2 Hot Water Heat / Reheat

A factory installed copper tube aluminum fin heat/reheat coil and two-way, 300 psig, modulating control valve shall be provided to control the flow of hot water for heating the leaving air.

2.13.3 Steam Heat / Reheat

A factory installed copper tube aluminum fin heat/reheat coil and two-way, 300 psig, modulating control valve shall be provided to control the flow of steam for heating the leaving air. (Steam trap and steam piping specialties shall be provided by others).

2.13.4 SCR Fired Heat / Reheat, Proportional Temperature Control

The electric heat/reheat shall be controlled through a “Zero firing” Silicon Controlled Rectifier (SCR) with an excluded aluminum heat sink and solid state logic systems to provide close control of the conditioned air temperature.

2.13.5 Head Pressure Control ( Low Ambient Control)

AIR COOLED – Low Ambient

2.13.5.1 -30°F, Flooded Control

The air cooled system shall incorporate a low ambient flooded head pressure control for year- round A/C system operation down to -30°F DB minimum ambient air temperature. Each refrigerant circuit shall be provided with a factory installed crankcase heater, cold-start relay,

QG-VFS0042 Rev - Page 12 of 15 liquid refrigerant receiver with receiver liquid level sight glass and head pressure regulating valve for flooded condenser option.

2.13.5 Water / Glycol Systems

2.13.5.1 Three-way, 150 psig Regulating Valves

Each refrigerant circuit’s head pressure shall be controlled by a factory installed, three-way water /glycol regulating valve rated for 150 psig. w.w.p.

2.13.5.2 Two-way, 350 psig Regulating Valves

Each refrigerant circuit’s head pressure shall be controlled by a factory installed, High Pressure two-way water /glycol regulating valve rated for 350 psig. w.w.p.

2.13.5.3 Three-way, 350 psig, Head Pressure Regulating Valves

Each refrigerant circuit’s head pressure shall be controlled by a factory installed high pressure Three-way water/ glycol regulating valve rated for 350 psig. w.w.p.

2.13.6 DX - Capacity Modulation/Freeze -Protection

2.13.6.1 Snap-Acting, Hot Gas Bypass (Models Available VFS-( )-AR, W & G

The CyberTWO floor A/C unit shall incorporate a hot gas bypass system to provide modulation of the units cooling capacity. This option shall also provide evaporator coil freeze protection under low load conditions.

2.13.7 Modulating Chilled Water Control Valves

2.13.7.1. Two-way, 400 psig Modulating Valve A 2-way modulating valve rated for a maximum 400 psig w.w.p. shall be factory piped and wired. The two-way chilled water modulating valve shall automatically meter the flow of chilled water to the cooling coil in response to a proportional signal (0-10 VDC) provided to the valve by the A-Tech-20 controller.

2.14 Accessories

2.14.1 Top Discharge Plenum Box (Upflow Units Only)

A 2 or 3-way plenum discharge box shall be provided. The plenum box shall include double – deflecting, adjustable grilles.

2.14.2 Adjustable Floor Stand:

An adjustable floor stand shall be provided to allow for ease of installation of the CyberTWO VFS A/C onto a raised floor. Floor stand height shall be adjustable and shall ship separately for field installed.

2.14.3 High Efficiency Filtration (Up to 95% Dust Spot Efficiency)

QG-VFS0042 Rev - Page 13 of 15 CyberTWO A/C’s are available with optional high efficiency IAQ conscious filtration. These 4" deep filters are available with dust spot efficiency ratings ranging from 45% to 95% based on ASHRAE Test Standard 52-76

2.14.4 Condensate Pump

A condensate pump shall be factory installed within the CyberTWO system (both up-flow and down-flow units) for automatic removal of condensate and humidifier flush water (if applicable). The condensate pump shall include an internal overflow safety float which, when wired to the VFS unit’s remote stop/start terminals, shall open the unit’s control circuit, thereby shutting the unit down in the event of a condensate overflow. The condensate pump shall be specifically designed to operate with the higher condensate temperatures caused by the flush and drain cycle of the electrode canister humidifiers.

The condensate pump shall have the capacity of ______gpm (l/s) at ______ft (kpa) of head.

2.14.5 Smoke Detection

A photo-electric smoke detector shall be factory installed and wired in the evaporator section of the suction side of the evaporator blower. The air conditioner will shut down upon sensing smoke in the return air stream.

2.14.6 Firestat

The air conditioner shall be provided with a factory wired and mounted firestat. The firestat will shut down the air conditioner upon sensing a high return air temperature.

2.14.7 Remote Water Detector – Spot Type

A remote single point water/leak detector shall be factory supplied and shall ship separately for field installation. Upon sensing a water leak, the normally closed water detector control circuit shall open, thereby shutting down the CyberTWO unit’s water producing components.

2.14.8 Remote Water Detector – Strip Type

A 20 ft. in length remote strip/cable type water/leak detector shall be provided for remote field installation. In addition to the 20 ft. sensing cable, a 24 volt water detector power module shall require field mounting and wiring to the factory provided terminal connection. Upon sensing a water leak, the normally closed water detector control circuit shall open, thereby shutting down the CyberTWO unit’s water producing components.

2.15 Energy $aving Options

A Free-Cooling economizer cycle shall be provided to take advantage of low ambient air temperature conditions to provide compressorless cooling. The air conditioner shall have three modes of operation:

2.16.1 100% Free-Cooling Mode:

QG-VFS0042 Rev - Page 14 of 15 A free-cooling cycle shall be provided to take advantage of low ambient air temperature conditions to provide compressorless cooling. When entering condenser water temperatures are below 55°F (setpoint adjustable) and cooling is required, source coolant shall be diverted from the DX water or glycol cooled refrigerant condenser to a chilled water / glycol coil (free-cooling coil and control valve). To maximize the cooling effect of the coolant solution during the free-cooling mode, the drycooler capacity shall be increased by reversing the typical drycooler fan(s) cycling sequence of operation. The free-cooling coil shall be closely sized to match the refrigerant cooling capacity to increase the number of hours that the system can operate in the free-cooling mode, thereby increasing the operating savings of the installation.

2.16.1.1 "Assist" FC + 1-Stage DX Mode:

When entering condenser water temperatures are below 55°F (setpoint adjustable) and cooling is required, the A-Tech-20 microprocessor controller’s “assist-mode” free-cooling program algorithm shall analyze input data from factory installed return air temperature and relative humidity sensor. Based on this data, the A-Tech-20 shall automatically activate partial pre-cooling mode in conjunction with one stage of DX cooling. This “pre-cooling” effect decreases the number of hours of compressor operation, thereby increasing savings of the installation.

2.16.1.2 100%, 2-Stage DX Cooling Mode:

When entering condenser water temperatures are above the Free Cool Enable setpoint plus adjustable hysterisis or at any time when the free-cooling mode (with Assist) cannot handle the cooling or dehumidification load, the A-Tech-20 shall automatically switch to 100%, 2-stage DX – water / glycol cooled compressorized cooling mode.

2.16.2 Alternative Water Source (chilled water by "Day" and DX-Backup by "Night" !)

An alternative water source cooling cycle shall be provided to utilize building chilled water supply when available as the primary cooling cycle with dual compressor, DX refrigerant cooling as a backup. The air conditioner shall have two cooling systems:

2.16.2.1 Primary Mode:

The primary code of cooling shall be chilled water/glycol circuit with alternative water source cooling coil and three-way modulating control valve rated for 400 psig. w.w.p.

2.16.2.2. Secondary / Backup Mode:

The secondary/backup mode of cooling shall be a dual compressor, DX refrigerant circuit. The A- Tech-20 microprocessor’s Alternative Water Source program algorithm shall analyze input data from factory provided and installed room air temperature and relative humidity sensors. Based on this data, the A-Tech-10 shall automatically control the sequencing of the primary AWS chilled water to and from the secondary /backup dual compressor DX modes of operation. If chilled water is available, the system will operate like a chilled water unit, without the compressor operating. When the water temperature is too high, or the water flow rate is not sufficient, the air conditioner automatically switches to the dual compressor, DX refrigerant cycle.

QG-VFS0042 Rev - Page 15 of 15