Carrier 25HPA Performance Series Installation Instructions Manual

Contents

8Connect Ground and Power WiresConnect ground wire to ground connection in control box forsafety. Connect power wiring to contactor as shown in Fig. 9.DISCONNECTPER N. E. C. AND/ORLOCAL CODESCONTACTORGROUNDLUGFIELD GROUNDWIRINGFIELD POWERWIRINGA91056Fig. 9 --- Line ConnectionsConnect Control WiringRoute 24v control wires through control wiring grommet andconnect leads to control wiring. See Thermostat InstallationInstructions for wiring specific unit combinations.Use No. 18 AWG color--coded, insulated (35°C minimum) wire.If thermostat is located more than 100 ft from unit, as measuredalong the control voltage wires, use No. 16 AWG color--coded,insulated wire to avoid excessive voltage drop.All wiring must be NEC Class 1 and must be separated fromincoming power leads.Use furnace transformer, fan coil transformer, or accessorytransformer for control power, 24v/40va minimum.NOTE: Use of available 24v accessories may exceed theminimum 40va power requirement. Determine total transformerloading and increase the transformer capacity or split the loadwith an accessory transformer as required.Final Wiring CheckIMPORTANT: Check factory wiring and field wire connectionsto ensure terminations are secured properly. Check wire routingto ensure wires are not in contact with tubing, sheet metal, etc.STEP 9 —Compressor Crankcase HeaterWhen equipped with a crankcase heater, furnish power to heater aminimum of 24 hr before starting unit. To furnish power to heateronly, set thermostat to OFF and close electrical disconnect tooutdoor unit.A crankcase heater is required if refrigerant tubing is longer than80 ft. Refer to the Long Line Guideline--Residential Split--SystemAir Conditioners and Heat Pumps.STEP 10 —Install Electrical AccessoriesRefer to the individual installation instructions packaged with kitsor accessories when installing.STEP 11 —Check OAT Thermistor and OCT ThermistorAttachmentsOutdoor Air Temperature (OAT) Thermistor is factory installedby inserting the nibs on either sides of the thermistor bodythrough a keyhole in the bottom shelf of the control box andlocking it in place by turning it 90 degrees, such that the sphericalend of a nib faces the front of the control box.Check to make sure the OAT is locked in place. See Fig. 10.OAT Thermistor must be locked inplace with spherical nib end facingtowards the front of the control boxA05408Fig. 10 --- Outdoor Air Thermistor (OAT) AttachmentThe Outdoor Coil Temperature (OCT) Thermistor is factoryinstalled on the 3/8” diameter stub tube located on the coilassembly.Check to make sure that it is securely attached with the clip asshown in Fig. 11.OCT Thermistormust be securedtight on stub tube.A05409Fig. 11 --- Outdoor Coil Thermistor (OCT) Attachment25HPA