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
Inspect all refrigerant tubing connections and the unit base for oil accumulations annually. Detecting oil generally indicates a refrigerant leak.
!WARNING
EXPLOSION, SAFETY AND ENVIRONMENTAL HAZARD
Failure to follow this warning could result in personal injury, death or equipment damage.
This system uses Puron
If oil is detected or if low cooling performance is suspected,
If no refrigerant leaks are found and low cooling performance is suspected, refer to Checking and Adjusting Refrigerant Charge section.
Evaporator Airflow
The heating and/or cooling
Puron Items
The indoor metering device is a TXV type device.
Pressure Switches
Pressure switches are protective devices wired into the control circuit (low voltage). They shut off compressor if abnormally high or low pressures are present in the refrigeration circuit. These pressure switches are specifically designed to operate with Puron
Loss of Charge/Low-Pressure Switch (Air Conditioner
Only)
This switch is located on the liquid line and protects against low suction pressures caused by such events as loss of charge, low airflow across indoor coil, dirty filters, etc. It opens on a pressure drop at about 20 psig (957 Pa). If system pressure is above this, switch should be closed.
To check switch:
1.Turn off all power to unit.
2.Disconnect leads on switch.
3.Apply ohmmeter 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 (0 Pa). Never open system without breaking vacuum with dry nitrogen.
High-Pressure Switch
The
To check switch:
1.Turn off all power to unit.
2.Disconnect leads on switch.
3.Apply ohmmeter 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
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
FIRE/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 a noise reducing shutdown device and 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 (26.3 kPa) and 625 (29.9 kPa) psig differential pressure.
Refrigerant
!WARNING
EXPLOSION, ENVIRONMENTAL HAZARD
Failure to follow this warning could result in personal injury, death or equipment damage.
This system uses Puron
This system uses Puron
Compressor Oil
The Copeland scroll compressor uses 3MAF POE oil. If additional oil is needed, use Uniqema
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