Water-Cooled Reciprocating Packaged Water Chillers
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Product Manual PM WHR Group: Chiller Effective: September 1997 Supersedes: PM 901 Water-Cooled Reciprocating Packaged Water Chillers WHR 017EW through WHR 210EW 60 Hertz Refrigerant R-22 © 1997 McQuay International Table of Contents Introduction ...............................................................................................3 Features and Benefits ................................................................................4 Design Advantages....................................................................................5 Selection Procedure...................................................................................9 Application Adjustment Factors.............................................................. 11 Performance Data ....................................................................................12 Part Load Data.........................................................................................18 Pressure Drop Curves..............................................................................19 Electrical Data .........................................................................................24 Physical Data...........................................................................................36 Dimensional Data....................................................................................41 Application Data......................................................................................45 Optional Features ....................................................................................48 Product Specifications.............................................................................52 Our Facility is "McQuay" is a registered trademarks of McQuay International 1997 McQuay International "Illustrations cover the general appearance of McQuay International products at the time of publication and we reserve the right to make changes in design and construction at anytime without notice" 2 WHR 017EW - 210EW Product Manual WHR Introduction The WHR packaged water chiller is a product of the McQuay commitment to offer energy efficient equipment design. A design approach carefully matching high quality compressors and shell-and-tube components into a unit of uncompromised operating efficiency. Efficiency • Compliance with ASHRAE 90.1 • Cross-circuit compressor unloading • Liquid subcooling • Copeland DISCUS compressor • Optional capacity reduction Reliability Rugged compressor design Factory installed operating and safety controls Flexibility • Complete factory assembly 25 available sizes Factory installed options Serviceability Semi-hermetic compressors Suction and discharge service valves Dual refrigerant circuits (WHR040 and above) Full Factory Testing • Assures trouble-free start-up and operation Product Manual WHR WHR 017EW - 210EW 3 Features and Benefits Efficiency All units are in full compliance with ASHRAE 90-1. Operating economy at reduced load is increased by operating each refrigerant circuit partially unloaded, rather than one circuit off and the other circuit fully loaded. At unloaded conditions each compressor will operate at lower compression ratios with substantial power savings. Optional steps of capacity reduction are accomplished by efficient cylinder unloading. Flexibility Completely factory assembled, piped, wired, and shipped in one piece ready for installation. Power to the single main supply power terminal block can be supplied by one field installed main supply power disconnect switch. The WHR packaged water chillers come in 25 sizes between 17 and 210 nominal tons (50 and 710 kW). Reliability WHR chillers use Copeland DISCUS semi-hermetic compressors. These compressors are designed for Refrigerant 22. All safety and operating controls are tested and calibrated at the factory. A complete set of safety controls for each circuit is used. Safety controls include compressor crankcase heater(s), freeze protection pressurestats (manual reset), oil switches (manual reset), high pressure safety switches (manual reset), and compressor motor overload protectors. Standard operating controls include time delay relays for 20-second sequence starting of compressors, manual pumpdown switches, low pressure controls, compressor lead-lag switches (WHR-040EW-210EW) and chilled water temperature controller. An optional control circuit transformer is available, eliminating the need for a separate 115V power supply to the controls. Serviceability Semi-hermetic, 1750 rpm induction type motors are used. The motors are refrigerant gas cooled. A finned motor housing helps dissipate motor heat. Solid-state modules in the motor terminal box respond to temperature sensors imbedded in all three motor windings to provide inherent thermal overload protection for all run and start conditions. Both suction and discharge service valves are provided to allow isolation of the compressor from the refrigerant circuit. All multiple compressor units use two independent refrigerant circuits. Dual refrigerant circuits permit shutdown and routine maintenance and service of one circuit while the second circuit maintains system operation. Full Factory Testing Each unit is pressure tested, evacuated and charged with Refrigerant 22. With the unit at full load, individual unit performance tests and extensive quality control checks are performed to ensure each control is properly adjusted and operates correctly. Each unit is then rechecked for refrigerant leakage. 4 WHR 017EW - 210EW Product Manual WHR Design Advantages Unit Arrangements Each unit consists of motor compressors, insulated evaporator and centralized electrical control panel containing all necessary safety and operating controls, and compressor starting controls. Units come complete with water-cooled condensers with integral subcooler circuits. Compressors WHR chillers use Copeland DISCUS semi-hermetic compressors. These compressors are designed for Refrigerant 22. Semi-hermetic, 1750 rpm induction type motors are used. The motors are refrigerant gas cooled. Solid-state modules in the motor terminal box respond to temperature sensors imbedded in all three motor windings, providing inherent thermal overload protection for all run and start conditions. The compressor housing is constructed from close grained, high nickel content, alloy cast-iron with no bolted joint between the motor and compressor. The housing includes a cast-iron cylinder head and stator cover, and a crankcase oil sightglass. A suction strainer built into the compressor in the gas stream between the suction service valve and the motor, filters out foreign and abrasive particles. An internal relief valve relieves discharge pressure to the suction side for safety protection at high compression ratios as required by ANSI/ASHRAE 15 Safety Code. Main bearings are solid cast bronze insert type with oversized bearing area resulting in ultra-low bearing loading. The crankshaft is die-forged, high strength iron alloy with integral counterweights, statically and dynamically balanced for smooth operation. Connecting rods are lightweight aluminum with integral bearing surfaces on the crankshaft and piston ends. Pistons are close grain cast iron with oil and compression rings. Piston pins are full floating type for long life. Compressors have a force-feed lubrication system with positive oil displacement, a reversible oil pump, and an operating oil charge. The pump feeds oil through rifle-drilled passages in the crankshaft to all bearing surfaces. Magnetic plugs trap particles that enter the crankcase. The oil supply filters through a large area oil strainer. During start-up, a crankcase heater minimizes oil being diluted by refrigerant. Factory Installed Liquid Line Components Each refrigerant circuit has a filter-drier, liquid line sightglass/moisture indicator, solenoid valve and thermal expansion valve. A manual liquid line shutoff valve, with charging connections, is supplied on all units with water-cooled condensers. Short Circuit Protection (WHR 017EW through 030EW, WHR 095EW through 210EW) Each compressor is individually protected against short circuit and locked rotor conditions by factory installed circuit breakers. The control circuit is protected by separate fusing. WHR-040EW through 090EW can have circuit breakers factory installed as an option. Product Manual WHR WHR 017EW - 210EW 5 Part Load Efficiencies Part load efficiencies and Integrated Part Load Values (IPLV) are calculated according to the requirements of the latest ARI Standard 590 and meet or exceed ASHRAE Efficiency Standard 90.1. Since most air conditioning systems operate at less than design full load a majority of the time, IPLV is an excellent method for comparing chillers efficiencies. Noise All McQuay WHR chillers are available with hot gas discharge line mufflers in each refrigerant circuit to reduce the overall sound levels. Systems using remote air-cooled condensers can transmit noise through the refrigerant piping, these units are supplied with discharge line mufflers as standard. Optional insulated acoustical compressor enclosure to further reduce sound levels is also available for most units. Unit Base Designed for easy handling , the units are mounted on a compact, rugged formed steel base. Isolator mounting holes are provided. Electrical Control Center Shipped with all operating and safety controls and motor starting equipment factory wired, operationally tested, and ready for operation. All controls are centrally located in a hinged control center with keylocked