Sterling GP Series specifications Optional Features, High Pressure Cutout, Flow Switch

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High Pressure Cutout

This electro-mechanical cutout device opens the compressor control circuit if the refrigeration system compressor discharge pressure exceeds 575 psi..

Note: The high-pressure cutout is a manual reset device typically mounted on the compressor discharge line inside the mechanical cabinet. Call a refrigeration service technician to analyze the problem and reset the control.

Low Pressure Cutout (no switch but done through the transducer)

This electro-mechanical cutout device opens the compressor control circuit if refrigeration system compressor suction pressure drops below 15 psi. It automatically resets when refrigerant suction pressure reaches 30 psi.

Note: The low pressure cutout is an automatic reset device typically mounted on the compressor suction line inside the mechanical cabinet. Call a refrigeration service technician to analyze the problem and reset the control.

Flow Switch

The thermal dispersion flow switch cutout device, mounted in the process piping, shuts down the chiller if it senses that the water/glycol flow rate through the evaporator has dropped below an acceptable level. The flow switch opens the control circuit and shuts down the pumps and the chiller.

Remote Start/Stop Interlock

An additional contact is provided to allow the remote starting or stopping of the chiller. To use this feature, remove the jumper between terminals X1 and 1, and supply a switch or dry contact interlock connected in series between these two terminals. Refer to the schematic inside the control enclosure door.

2-5 Optional Features

Options marked with “*” indicate options that can be factory installed or retrofitted in the field.

Automatic Water Make-Up*.Not available on chillers less reservoir tank. Includes an electric water solenoid valve, a level sensing pressure switch mounted in the reservoir tank, and the necessary internal piping to connect the chiller to a make-up water source. See Appendix for typical piping diagrams.

Caution! Customer piping must provide backflow protection and venting of tank to atmosphere to prevent over-pressurization of the reservoir tank (not needed for open tank). See Error! Reference source not found. on page Error! Bookmark not defined..

Process Water Sidestream Filter*. Not available on chillers less pump and reservoir tank. Includes a 50 micron filter, flow meter, ball valve for throttling water flow, and the necessary piping to provide constant filtering of the process water at about one gallon per minute (1 gpm/3.8lpm).

General Fault Indicator Audible/Visual Alarm*. Includes a 100 dB audible alarm horn/ visual alarm strobe and silence button with provisions for customer wiring indication

GP Series Portable Chillers

Chapter 2: Functional Description

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Contents GP Series Portable Chillers Shipping Information Table of Contents Maintenance How to Use This Manual SafetySafety Symbols Used in this Manual Responsibility General Description Functional DescriptionModels Covered in This Manual Chilled Water CircuitMechanical Features Standard FeaturesElectrical Features Controller Features Safety Devices and InterlocksRefrigeration Features Other FeaturesHigh Pressure Cutout Optional FeaturesFlow Switch Remote Start/Stop InterlockMounting Features Optional Pump Amperages Voltage Construction Full Load Amps Uncrating InstallationElectrical Connections Galvanic Corrosion Considerations Process Water ConnectionsBypass Valve Considerations Water Treatment ConsiderationsWater-Cooled Chiller Condensers Condenser ConsiderationsAir-Cooled Chiller Condensers Water Pumps Three-Phase CompressorsChecking Motor Direction Condenser FanWater Reservoir Part Number DescriptionEthylene Glycol and Propylene Glycol Curves Automatic Water Make-Up Option Finishing Setup Setting Up PasswordsInitial Start-Up Page Page Operation Panel Buttons, Indicator Lights, and SwitchesMicroprocessor Controller Main Status Screen Operator Setpoints Screen Status Screens Access Levels Page Controller Setpoints Menu Screen Alarms Optional CommunicationsGP Series Portable Chillers Operation Lubrication MaintenanceFilter Cleaning Maintaining the CondenserMaintaining the Evaporator Preventative Maintenance ServiceEvaporator Process Piping Y-Strainer Troubleshooting GP Series Portable Chillers TroubleshootingGP Series Portable Chillers Troubleshooting Returned Material Policy Warranty ReturnsAppendix Credit ReturnsParts Department Service DepartmentTechnical Assistance Sales DepartmentSpecifications Air-Cooled Portable ChillersPAC-40 Water-Cooled Portable Chillers PWC-20PWC-50 Pump Curves, Flow, and Pressure Considerations Hertz Pump CurvesCalculating Chiller Nominal Flow and Pressure to Process Electrical Schematic