HP A0554832 manual General Description, Chilled Water Circuit, Refrigeration Circuit

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2-2 General Description

Our portable chillers are reliable, accurate, and easy to use process cooling units. They are available in air-, water-, and remote air-cooled designs in a range of sizes from 2 to 40 tons. All are self-contained, fully portable and shipped ready to use. (Remote air-cooled chillers require field installation by qualified technicians.)

Standard range of operation is 30ºF to 65ºF (-1ºC to 18ºC) for applications using a water/glycol mix and 45ºF to 65ºF (7º to 18ºC) for water only applications.

A factory installed crankcase pressure regulating valve option is available for processes requiring a leaving water temperature of up to 75ºF (24ºC).

Chilled Water Circuit

Cooling water “To Process” and “From Process” connections are made at the gate valves provided outside the unit. Warm coolant (water and glycol mixture) returns from the process and goes into the reservoir tank. The coolant is then pumped through the evaporator where it is cooled. The coolant flows to the process and returns to repeat the cycle.

A pressure actuated process water bypass valve located between the supply line and reservoir tank (single pump models only) allows minimal flow through the unit during the intermittent fluctuating flow conditions. It is not intended to provide continuous full bypass flow.

This minimal flow allows the temperature sensor to signal the controller to shut down the compressor because of the drop in process water temperature. Typically the flow switch shuts down the chiller in this low flow condition.

The 2 hp and 3 1/2 hp models have a 1/4” poly-tubing constant bypass to provide additional process water bypass to prevent system freeze-up.

Refrigeration Circuit

Air-, water-, and remote air-cooled refrigerant condensing differs only in the way the compressed gas is condensed to a liquid.

Liquid refrigerant from the condenser heat exchanger flowing in the liquid line passes through a shut-off valve (5 hp to 40 hp chillers only) into a filter/dryer that removes moisture and other contaminants. A refrigerant sight glass is provided. The refrigerant then passes through the thermal expansion valve, which allows the refrigerant to expand (boil off) and cool the fluid inside of the evaporator. The refrigerant gas flows through the suction linen back into the compressor.

The refrigerant is compressed in the compressor and flows through the discharge line as a gas to the condenser. There it gives up its heat as it condenses to a liquid in the condenser.

A hot gas bypass valve is used to control cooling capacity during intermittent or partial load conditions. This feature contributes substantially to chiller longevity by eliminating excessive cycling of the compressor and providing close temperature control.

2-40 HP Portable Chillers

Chapter 2: Functional Description

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Contents Hp Portable Chillers Shipping Information Table of Contents Operation HP Portable Chillers Safety How to Use This ManualSafety Symbols Used in this Manual Responsibility Wear Safety Glasses and Work GlovesModels Covered in This Manual Functional DescriptionGeneral Description Chilled Water CircuitRefrigeration Circuit Standard Features Mechanical FeaturesOther Mechanical Features Refrigeration Features Electrical FeaturesController Features Other FeaturesHigh/Low Thermostat Control Safety Devices and InterlocksCrankcase Heater High Pressure CutoutFan Cycling Switch Oil Pressure Safety SwitchPressure Switch Flow SwitchOptional Features Mounting Features Optional Pump Amperages Voltage Construction Full Load Amps Installation UncratingElectrical Connections Bypass Valve Considerations Process Water ConnectionsGalvanic Corrosion Considerations Water Treatment ConsiderationsCondenser Considerations Water-Cooled Chiller CondensersAir-Cooled Chiller Condensers Remote Air-Cooled Chiller Condensers Page Equivalent Length in Feet for Valves and Fittings Refrigerant Charge Determination Chiller Condenser Charge Field Installed Piping ChargeChecking Motor Direction Three-Phase CompressorsWater Pumps Condenser FanPart Number Description Water ReservoirEthylene Glycol and Propylene Glycol Curves Automatic Water Make-Up Option Initial Start-Up E5CK Controller Indicator Name Description Panel Buttons, Indicator Lights, and SwitchesOperation Microprocessor ControllersSterlco 2000 Controller Indicator Name Description Indicator Name Description2000 Graphic Panel See on Indicator Name DescriptionIndicator Name Description With Sterlco 2000 Controller Typical Graphic Panels With E5CK ControllerAuto-Tuning Setting the Process Water TemperaturesStart-up Optional CommunicationsProgramming the Electronic High/Low Thermostat Thermostat Buttons Indicator Name DescriptionStage 2 High Temperature Protection Select Fahrenheit or CelsiusStage 1 Freeze Protection Maintenance Filter CleaningLubrication Maintaining the Evaporator Maintaining the CondenserEvaporator Process Piping Y-Strainer Air- and Remote Air-Cooled ChillersPreventative Maintenance Service HP Portable Chillers Troubleshooting TroubleshootingHP Portable Chillers Troubleshooting Appendix WarrantyTechnical Assistance Service DepartmentParts Department Sales DepartmentHp and 3 1/2 hp Air-Cooled Portable Chillers Drawings and SpecificationsHp and 7.5 hp Air-Cooled Portable Chillers Hp and 15 hp Air-Cooled Portable Chillers 20 hp, 25 hp, and 30 hp Air-Cooled Portable Chillers Hp and 3.5 hp Water-Cooled Portable Chillers Nominal Condenser water Nominal cooling Water ComIn. NPT Height Width Depth Lbs Hp and 7.5 hp Water-Cooled Portable Chillers Hp and 15 hp Water-Cooled Portable Chillers 20 hp, 25 hp, and 30 hp Water-Cooled Portable Chillers Hp and 40 hp Water-Cooled Portable Chillers Hp and 7.5 hp Remote Air-Cooled Portable Chillers Nominal cooling Com Refrigeration Power in amps e12.8 17.3 748Nominal cooling Com Refrigeration Hp and 15 hp Remote Air-Cooled Portable ChillersPres Nom Connections 15.0 40.9 34.0 74.7To/from No tank Tank, to/from Height Width Depth Lbs Hp through 40 hp Remote Air-Cooled Portable Chillers‘A’in ‘B’in ‘C’in ‘D’in ODSin Remote Condenser Assembly ModelsHertz Pump Curves Pump Curves, Flow, and Pressure ConsiderationsDWG. No. S0554823 Calculating Chiller Nominal Flow and Pressure to Process Water Pressure Drop TablesRecirculation Pump Specifications Recirc. power Flow Rate ∆ pressure Gpm Lpm Psi KPaFlow and Pressure Considerations Remote Air-Cooled Chiller Configurations Configuration aConfiguration B Configuration C Typical Ductwork for Air-Cooled Chillers Central and Gravity Return Piping with Standpipe Diagram Piping DiagramsTypical Piping Schematic, 2 and 3 1/2 hp Models HP Portable Chillers Appendix HP Portable Chillers Appendix Typical Piping Schematic, 5 hp through 40 hp, No-Pump Models HP Portable Chillers Appendix Time-delay Relays Disconnect Switch Optional Electrical SchematicsTypical Electrical Subpanel Speed FusesTypical Electrical Schematic, 2 hp and 3 1/2 hp Models A0554815 Typical Power Wiring Schematic, 5 hp through 40 hp ModelsHP Portable Chillers Appendix DWG A0554931 DWG A0562343 DWG A0562435 Typical Wiring Schematic, 35 hp and 40 hp Models with Pump DWG A0562434
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