Addison RCA051, Installation, Operation And Maintenance Manual

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21
GENERAL SERVICE GUIDE
SYMPTOM POSSIBLE TROUBLE METHOD OF FINDING
Compressor
Will Not Start. Power off, loose electrical connections or fuse open.
Compressor contactor not closing.
Internal compressor thermal overload open.
Compressor defective.
High or low pressure switch open or defective.
Oil pressure control open or defective. Check disconnect switch, fuses and wiring.
Check voltage to contactor coil, transformer slave relay, thermostat.
If compressor is hot, allow 2 hours to cool – see below.
Check compressor for electrical failure. Compressor may be seized, check for L.R.A.
Check calibration of high or low pressure switch.
Check oil failure control – see below.
Compressor
Starts But Cuts
Out On Low
Pressure Switch.
Low on refrigerant.
Airflow restricted.
Restriction in liquid line.
Defective low pressure switch. Check sightglass and check pressures.
Check for dirty evaporator coil, dirty filters, dampers closed, iced evaporator, improper belt
tension, broken belt, check motor amps, duct design.
Check head pressure, check and adjust TXV if not functioning properly, check pressure
drop across filter drier.
Check calibration of switch.
Compressor
Starts But Cuts
Out On High
Pressure Switch. Refrigerant overcharged.
Condenser fan control has incorrect setting.
Fan motor defective.
Condenser coil inlet obstructed or dirty.
Air or non-condensables in system.
Defective high pressure switch.
Restriction in discharge or liquid line. Check pressures, charge by subcooling.
Check calibration of the low ambient control.
Check fan motor.
Check coil and inlet clearances and for possible air re-circulation.
Check high side equalized pressure reading with equivalent outdoor temperature.
Check calibration of switch.
Check discharge and liquid line pressures, check TXV.
Compressor
Cuts Out On
Thermal Overload. Low voltage.
Sustained high discharge pressure.
High suction and discharge pressures.
Defective compressor overload.
Defective run capacitor.
Improper refrigerant charge.
Bearings or pistons too tight.
Allow time for compressor to cool. Check voltage.
Check running amperage and conditions described under high discharge pressure.
Check TXV setting, check for air in system.
Allow compressor to cool for two hours if compressor is hot. Recheck for open circuit.
Check run capacitor for compressor and fan motor.
Check subcooling.
Check for low oil level.
Check dome temperature of compressor.
Compressor
Cuts Out On Oil
Failure Control
(Semi-Hermetic). Low oil level.
Defective oil pump.
Defective control.
Liquid refrigerant is entering crankcase. Check crankcase bull’s-eye – add to have oil level midway in sightglass.
Check pump.
Check oil failure control for calibration.
Compressor will be wet. Check crankcase heater or cause for liquid feedback.
Noisy
Compressor. Scroll compressors are rotation sensitive.
Refrigerant overcharged.
Excess or insufficient oil in compressor crankcase.
Liquid floodback.
Tubing rattle.
Compressor defective.
Reverse wiring at disconnect switch may require blower be rechecked for rotation.
Check pressures and subcooling.
Check oil level on hermetic compressors, check total equivalent feet of piping, add oil
as recommended.
Check TXV setting. Refrigerant overcharge refrigerant circuit problem.
Dampen by taping or clamping, bend tubing away from contact where possible.