Carrier 48EZ(N)-A Outdoor Fan, Electrical Controls and Wiring, Refrigerant Circuit

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48EZ -- A

BLOWER

HOUSING

2 SETSCREWS

(HIDDEN)

C99085

Fig. 19 - Removal of Motor and Blower Wheel

A07680

Fig. 20 - Burner Rack Removed

FEEDER TUBE

STUB TUBE

DEFROST

THERMOSTAT

C99029

Fig. 21 - Defrost Thermostat Location

A07680

Fig. 22 - Burner Rack Removed

Outdoor Fan

!CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in damage to unit components.

Keep the outdoor fan free from all obstructions to ensure proper cooling operation. Never place articles on top of the unit.

1.Remove 6 screws holding outdoor grille and motor to top cover.

2.Turn motor/grille assembly upside down on top cover to expose the fan blade.

3.Inspect the fan blades for cracks or bends.

4.If fan needs to be removed, loosen the setscrew and slide the fan off the motor shaft.

5.When replacing fan blade, position blade back to the same position as before.

6.Ensure that setscrew engages the flat area on the motor shaft when tightening.

7.Replace grille.

Electrical Controls and Wiring

Inspect and check the electrical controls and wiring annually. Be sure to turn off the gas supply, and then the electrical power to the unit.

Remove access panels (see Fig. 18) to locate all the electrical controls and wiring. Check all electrical connections for tightness. Tighten all screw connections. If any discolored or burned connections are noticed, disassemble the connection, clean all the parts, re-strip the wire end and reassemble the connection properly and securely.

After inspecting the electrical controls and wiring, replace the access panels (see Fig. 18). Start the unit, and observe at least one complete heating cycle and one complete cooling cycle to ensure proper operation. If discrepancies are observed in any operating cycle, or if a suspected malfunction has occurred, check each electrical component with the proper electrical instrumentation. Refer to the unit wiring label when making these checkouts.

NOTE: Refer to the heating and/or cooling sequence of operation in this publication as an aid in determining proper control operation.

Refrigerant Circuit

Annually inspect all refrigerant tubing connections and the unit base for oil accumulations. Detecting oil generally indicates a refrigerant leak.

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Contents Table of Contents Safety ConsiderationsCheck Equipment Receiving and InstallationIntroduction Provide Unit Support48EZ-A24-36 Unit Dimensions 48EZ-A42-60 Unit Dimensions Roof Curb Dimensions NumberRig and Place Unit Field Fabricate DuctworkProvide Clearances InspectionConnect Condensate Drain Install Flue HoodInstall Gas Piping Rigging/Lifting of Unit See FigFire or Explosion Hazard Sediment TrapInstall Duct Connections Configuring Units for Downflow Vertical DischargePhysical Data Unit 48EZ-A Maximum Gas Flow Capacity Physical Data Unit 48EZ-A Cont’dHeating Inputs High-Voltage Connections Install Electrical ConnectionsSpecial Procedures for 208-V Operation Unit Component Damage HazardControl Voltage Connections Balance Point Setting-Thermidistat or Hybrid ThermostatPRE-START-UP Transformer ProtectionCheck for Refrigerant Leaks Start-up Heating and Make Adjust- mentsSTART-UP Unit Sequence of OperationCheck Gas Input Adjust Gas InputUnit Damage Hazard Start-up Cooling and Make Adjust- ments Gas Heating Fan Speed Set-up Checking and Adjusting Refrigerant ChargeIndoor Airflow and Airflow Adjustments Unit Operation HazardContinuous Fan Operation Two Cooling Fan Speeds Set-up Dehumidification feature usedColor Coding for Indoor Fan Motor Leads Unit Heating Rise Motor Dry Coil Air Delivery* Horizontal Unit 48EZ-A24-60Range Speed Color Dry Coil Air Delivery* Horizontal Discharge Unit 48EZ-A24-60 1354 1290 1226 1158 1102 1046 981 918 843 55oF Heating Rise Medium1 48EZ ---,NA48090 48EZ ---,NA48130 Unit Heating Rise Motor Wire Downflow Cooling Standard CFM Scfm Economizer + Tons Horizontal and Downflow Filter Pressure Drop Table IN. W.CUnit Standard CFM Scfm Size Cooling Standard CFM Scfm48EZ a 208/230-1-60 Ladder Wiring Diagram, Unit 48EZ-A 208/230-3-60 Connection Wiring Diagram, Unit 48EZ-A Cont. 208/230-3-60 Ladder Wiring Diagram, Unit 48EZ-A Cooling Charging Table-Subcooling Air Filter MaintenanceCleaning the Blower Motor and Wheel Indoor Blower and MotorBurner Ignition Limit SwitchInduced Draft combustion air Blower Assembly Main BurnersOutdoor Fan Electrical Controls and WiringRefrigerant Circuit Gas Input Pressure SwitchesLoss of Charge Switch Indoor AirflowCopeland Scroll Compressor Puron Refrigerant High-Pressure SwitchExplosion Hazard Refrigerant System Unit Operation and Safety HazardCompressor Oil START-UP Checklist TroubleshootingPuronr R-410A Quick Reference Guide Troubleshooting Guide Cooling or Heat Pump Heating Mode Symptom Cause RemedyTroubleshooting Guide-LED Error Codes Troubleshooting Guide-HeatingLED OFF Preliminary Information Model no TemperaturesRemove and Store in Job Files III. START-UP Electrical Supply Voltage Compressor Amps