Carrier GT-PX Split Series Installation, Operation & Maintenance Instructions Manual

R e s i d e n t i a l S p l i t - 6 0 H z R 2 2 & R 4 1 0 AR e v. : 5 J u n e , 2 0 0 832 W a t e r- S o u r c e H e a t i n g a n d C o o l i n g S y s t e m sElectrical - Low Voltage WiringFrom Water SourceINOUTNOTE: Shut-off valves, strainers andother required components not shown.SolenoidValve FlowRegulatorTo DischargeStage 1Stage 2Figure 27: Two-Stage PipingELECTRICAL - THERMOSTAT WIRINGThermostat InstallationThe thermostat should be located on an interior wall in alarger room, away from supply duct drafts. DO NOT locatethe thermostat in areas subject to sunlight, drafts or onexternal walls. The wire access hole behind the thermostatmay in certain cases need to be sealed to prevent erroneoustemperature measurement. Position the thermostat backplate against the wall so that it appears level and so thethermostat wires protrude through the middle of the backplate. Mark the position of the back plate mounting holesand drill holes with a 3/16” (5mm) bit. Install suppliedanchors and secure plate to the wall. Thermostat wiremust be 18 AWG wire. Wire the appropriate thermostat asshown in Figures 28a and 28b to the low voltage terminalstrip on the CXM control board. Practically any heat pumpthermostat will work with these units, provided it has thecorrect number of heating and cooling stages.YOGRCYOGRCW1W2WETypicalAir HandlerTypicalT-statCXM Board(CompressorSection)OY/Y2GRCLAL1OptionalJumperYOGRCY1OGRCW1W2WETypicalAir HandlerTypicalT-statCXM Board(CompressorSection)OGRCLAL1Y2Y1Y/Y2From CompressorSolenoid ValveFigure 28b: Typical Thermostat Wiring, Single-StageUnits (2 Heat/1 Cool)Figure 28a: Typical Thermostat Wiring, Two-Stage Units(3 Heat/2 Cool)ѥ CAUTION! ѥCAUTION! Refrigerant pressure activated water regulatingvalves should never be used with Carrier Geothermalequipment.ѥ CAUTION! ѥCAUTION! Many units installed with a factory or fieldsupplied manual or electric shut-off valve. DAMAGE WILLOCCUR if shut-off valve is closed during unit operation. Ahigh pressure switch must be installed on the heat pumpside of any fi eld provided shut-off valves and connected tothe heat pump controls in series with the built-in refrigerantcircuit high pressure switch to disable compressor operationif water pressure exceeds pressure switch setting. The fieldinstalled high pressure switch shall have a cut-out pressureof 300 psig and a cut-in pressure of 250 psig. This pressureswitch can be ordered from Carrier Geothermal with a 1/4”internal flare connection as part number 39B0005N02.