Carrier 48EZ(N)-A High-Pressure Switch, Copeland Scroll Compressor Puron Refrigerant

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48EZ -- A

C99097

Fig. 24 - Refrigerant Circuit

2.Disconnect leads on switch.

3.Apply ohm meter leads across switch. You should have continuity on a good switch.

NOTE: Because these switches are attached to refrigeration system under pressure, it is not advisable to remove this device for troubleshooting unless you are reasonably certain that a problem exists. If switch must be removed, remove and recover all system charge so that pressure gauges read 0 psi. Never open system without breaking vacuum with dry nitrogen.

High-Pressure Switch

The high-pressure switch is located in the discharge line and protects against excessive condenser coil pressure. It opens at 650 psig.

High pressure may be caused by a dirty outdoor coil, failed fan motor, or outdoor air recirculation. To check switch:

1.Turn off all power to unit.

2.Disconnect leads on switch.

3.Apply ohm meter leads across switch. You should have continuity on a good switch.

Copeland Scroll Compressor (Puron Refrigerant)

The compressor used in this product is specifically designed to operate with Puron (R-410A) refrigerant and cannot be interchanged.

The compressor is an electrical (as well as mechanical) device. Exercise extreme caution when working near compressors. Power should be shut off, if possible, for most troubleshooting techniques. Refrigerants present additional safety hazards.

!WARNING

EXPLOSION HAZARD

Failure to follow this warning could result in personal injury or death and/or property damage.

Wear safety glasses and gloves when handling refrigerants. Keep torches and other ignition sources away from refrigerants and oils.

The scroll compressor pumps refrigerant throughout the system by the interaction of a stationary and an orbiting scroll. The scroll compressor has no dynamic suction or discharge valves, and it is more tolerant of stresses caused by debris, liquid slugging, and flooded starts. The compressor is equipped with an internal pressure relief port. The pressure relief port is a safety device, designed to protect against extreme high pressure. The relief port has an operating range between 550 and 625 psig differential pressure.

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Contents Table of Contents Safety ConsiderationsReceiving and Installation IntroductionCheck Equipment Provide Unit Support48EZ-A24-36 Unit Dimensions 48EZ-A42-60 Unit Dimensions Roof Curb Dimensions NumberField Fabricate Ductwork Provide ClearancesRig and Place Unit InspectionInstall Flue Hood Install Gas PipingConnect Condensate Drain Rigging/Lifting of Unit See FigFire or Explosion Hazard Sediment TrapInstall Duct Connections Configuring Units for Downflow Vertical DischargePhysical Data Unit 48EZ-A Physical Data Unit 48EZ-A Cont’d Maximum Gas Flow CapacityHeating Inputs Install Electrical Connections Special Procedures for 208-V OperationHigh-Voltage Connections Unit Component Damage HazardBalance Point Setting-Thermidistat or Hybrid Thermostat PRE-START-UPControl Voltage Connections Transformer ProtectionStart-up Heating and Make Adjust- ments START-UPCheck for Refrigerant Leaks Unit Sequence of OperationAdjust Gas Input Check Gas InputUnit Damage Hazard Start-up Cooling and Make Adjust- ments Checking and Adjusting Refrigerant Charge Indoor Airflow and Airflow AdjustmentsGas Heating Fan Speed Set-up Unit Operation HazardTwo Cooling Fan Speeds Set-up Dehumidification feature used Continuous Fan OperationColor Coding for Indoor Fan Motor Leads Dry Coil Air Delivery* Horizontal Unit 48EZ-A24-60 Unit Heating Rise MotorRange 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 Horizontal and Downflow Filter Pressure Drop Table IN. W.C Unit Standard CFM Scfm SizeDownflow Cooling Standard CFM Scfm Economizer + Tons 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 Maintenance Cleaning the Blower Motor and WheelAir Filter Indoor Blower and MotorLimit Switch Induced Draft combustion air Blower AssemblyBurner Ignition Main BurnersElectrical Controls and Wiring Outdoor FanRefrigerant Circuit Pressure Switches Loss of Charge SwitchGas Input Indoor AirflowHigh-Pressure Switch Copeland Scroll Compressor Puron RefrigerantExplosion Hazard Unit Operation and Safety Hazard Refrigerant SystemCompressor Oil Troubleshooting START-UP ChecklistPuronr R-410A Quick Reference Guide Troubleshooting Guide Cooling or Heat Pump Heating Mode Symptom Cause RemedyTroubleshooting Guide-Heating Troubleshooting Guide-LED Error CodesLED OFF Temperatures Remove and Store in Job FilesPreliminary Information Model no III. START-UP Electrical Supply Voltage Compressor Amps