Sterling 882.93092.01 manual Refrigeration Circuit, System Control

Page 9

Refrigeration Circuit

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

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.

Liquid refrigerant from the condenser heat exchanger flowing in the liquid line passes through a shut-off valve into a filter/dryer that removes moisture and other contaminants. After the filter/dryer the refrigerant passes through a solenoid valve to prevent liquid migration when the compressor is off. A refrigerant sight glass is provided to view the flow of liquid refrigerant, and to view if the system is free of moisture. The refrigerant then passes through the thermal expansion valve, which allows the refrigerant to expand (boil off) and cool (remove the heat from) the fluid inside of the evaporator.

From the evaporator the refrigerant gas flows through the suction line back into the compressor.

A modulating electronic 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.

System Control

Putting this all together, the controller maintains the desired leaving fluid temperature using multiple inputs to determine if, when and for how long the compressor(s) are on, and if, when, the percent open and for how long the modeling hot gas bypass valve is on.

Once the unit’s power is enabled and the controller is turned on (see Chapter 4 for more details on the operation of the controller) it verifies there is sufficient fluid level in the tank (if present). If there is not enough fluid in the tank the controller will warn the user, or fill the tank with water from a connected source if equipped with the optional automatic water makeup valve. See Chapter 3 for more information regarding the initial setup and startup of the unit.

Once the tank level is satisfied and the start button is pressed, the process pump turns on and provides flow to the process. The controller verifies the flow through the electronic flow switch. If the flow is not established within 10 seconds the controller will alarm and disable the refrigeration circuit. Upon flow verification the controller uses the leaving fluid temperature and the setpoint temperature to determine the operation of the compressor(s). When the leaving fluid temperature is greater than the setpoint plus the “compressor on

GP Series Portable Chillers

Chapter 2: Functional Description

9 of 90

Page 8 Page 10
Image 9
Page 8 Page 10
Contents GP Series Portable Chillers Shipping Information Table of Contents Chapter Troubleshooting 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 Typical ApplicationsChilled Water Circuit System Control Refrigeration CircuitMechanical Features Standard FeaturesRefrigeration Features Electrical FeaturesController Features Safety Devices and InterlocksOther Features Crankcase HeaterHigh Pressure Cutout Optional Features Flow SwitchRemote Start/Stop Interlock Mounting Features Installation UncratingElectrical Connections Bypass Valve Considerations Process Water ConnectionsWater Treatment Considerations Galvanic Corrosion ConsiderationsCondenser Considerations Water-Cooled Chiller CondensersAir-Cooled Chiller Condensers Typical GP20-50 Water Cooled Condenser ConnectionsRemote Air-Cooled Chiller Condensers Towards the condenser GPRC-40 GPRC-105 Discharge Line Sizing Refrigerant Charge Determination Remote Condenser Configurations Checking Motor Direction Three-Phase CompressorsWater Pumps Condenser FanPart Number Description Water ReservoirSuggested Overhead Piping Configuration Pump Initial Start-Up Automatic Water Make-Up OptionPage Finishing Setup Setting Up Passwords Supervisor Password to complete the security setup Panel Buttons, Indicator Lights, and Switches OperationMicroprocessor Controller Main Status Screen Operator Setpoints Screen Status ScreensMain Chiller Status Screen GP Series Portable Chillers Operation Page Controller Setpoints Access LevelsGP Series Portable Chillers Operation Menu Screen Operator Setpoints Screen These configurations are described below Configuration SettingsWEB Optional Communications AlarmsFilter Cleaning MaintenanceLubrication Maintaining the CondenserPreventative Maintenance Service Maintaining the EvaporatorEvaporator Process Piping Y-Strainer Identifying the Cause of a Problem TroubleshootingGP Series Portable Chillers Troubleshooting SC/W System fault GP Series Portable Chillers Troubleshooting Problem Possible cause Solution Non-Controller Related IssuesGP Series Portable Chillers Troubleshooting GP Series Portable Chillers Troubleshooting Appendix Returned Material PolicyTechnical Assistance Service Department Sales DepartmentContract Department Air-Cooled Portable Chillers SpecificationsGPAC-40 GPAC-70 GPAC-105 GPAC-175 GPWC-20 Water-Cooled Portable ChillersGPWC-40 GPWC-70 GPWC-105 GPWC-175 Hertz Pump Curves Pump Curves, Flow, and Pressure ConsiderationsALL 60 Hz ALL 50 Hz ALL 50 Hz Calculating Chiller Nominal Flow and Pressure to Process Remote Air-Cooled Chiller Configurations Double Riser Detail Typical Ductwork for Air-Cooled Chillers Water column = Pascal GP Series Portable Chillers Appendix Piping Diagrams GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix

882.93092.01 specifications

The Sterling 882.93092.01 is an impressive timepiece that exemplifies the perfect blend of artistry and precision engineering. This elegant watch is a testament to the craftsmanship that defines the Sterling brand, making it a sought-after choice for both watch aficionados and casual wearers alike.

One of the main features of the Sterling 882.93092.01 is its exceptional movement technology. This watch is powered by a reliable automatic movement, ensuring accurate timekeeping without the need for battery replacements. The self-winding mechanism harnesses the natural motion of the wearer's wrist, providing a seamless and hassle-free experience.

The design of the Sterling 882.93092.01 is another standout characteristic. The watch features a stainless steel case that provides durability and a sleek aesthetic. The polished finish adds a touch of sophistication, making it suitable for both formal and casual settings. With a diameter that fits comfortably on the wrist, it is designed for effortless wear throughout the day.

Additionally, the face of the Sterling 882.93092.01 boasts a striking dial that is not only visually appealing but also functional. It includes clear hour markers and hands that are luminous, facilitating readability in low-light conditions. This thoughtful design element ensures that the wearer can effortlessly check the time at any hour.

Another notable aspect is the watch's water resistance. The Sterling 882.93092.01 is rated for water resistance, making it suitable for everyday wear, including light swimming and exposure to splashes. This feature enhances the watch’s practicality, allowing it to withstand the rigors of daily life without compromising its integrity.

Finally, the bracelet of the Sterling 882.93092.01 is crafted with comfort and style in mind. It features an adjustable clasp that allows for a customized fit, ensuring that the watch remains secure on the wrist. The combination of high-quality materials and impeccable design makes the bracelet an integral part of the overall charm of the watch.

Overall, the Sterling 882.93092.01 is more than just a timekeeping device; it is a statement piece that showcases exceptional design, reliable technology, and outstanding craftsmanship. Whether worn at special occasions or in everyday scenarios, this watch is bound to impress and stand the test of time.
Top Page Image Contents