Addison RCA051, Инструкция по установке, эксплуатации и обслуживанию

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GENERAL SERVICE GUIDE Continued
SYMPTOM POSSIBLE TROUBLE METHOD OF FINDING
Noisy Operation. Blower rotational noise.
Air noise.
Chattering contactor.
Tubing rattle. Check blower, motor and drive for faulty adjustment or noisy bearings, loose parts, blower out of
balance.
Check ductwork. Air Velocity too high.
Check for adequate control voltage, check for shorts or breaks, check thermostat, check contactor
points.
Dampen by taping or clamping, bend tubing away from contact where possible.
High Suction
Pressure. Excessive load on evaporator coil.
Broken compressor valves. Scroll compressors do not
have valves.
Compressor is unloaded.
Leaking check valve.
Expansion valve not secured to suction line or TXV defective.
Check for high entering wet bulb temperature. Check for excessive airflow.
Scroll compressors should not be pumped down below 5 PSI.
Recalibrate unloader pressure switch.
Check temperature across check valve.
Check the TXV, ensure bulb is insulated.
High Discharge
Pressure. TXV setting.
Air inlet to condenser dirty or obstructed.
Condenser fan, motor defective.
Condenser fan control has incorrect setting. Check TXV setting and calibrate superheat.
Check for proper clearances and possible air recirculation.
Check condenser fan motor and run capacitor.
Check calibration of low ambient head pressure control.
Suction Pressure
Too Low. Refrigerant undercharge.
Blower running backwards.
Loose blower pulley or belts.
Defective or improperly adjusted expansion valve.
Dirty filter.
Too little airflow or low entering air temperature.
Restriction in suction or liquid line. Check pressures and subcooling.
Interchange any two wires from 3 phase disconnect.
Check drive, pulley alignment, belt tension.
Check superheat and adjust TXV.
Check filter and evaporator coil.
Check airflow and entering air wet bulb conditions.
Check refrigerant circuit for restriction.
Head Pressure
Too Low. Insufficient refrigerant charge.
Defective or improperly adjusted expansion valve.
Low suction pressure.
Condenser fan control setting.
Defective compressor. Check subcooling, check for leak.
Check superheat and adjust TXV.
See above – suction pressure too low.
Check calibration of low ambient control.
See above – high suction pressure.
Compressor
Short Cycles. Thermostat location or malfunction.
Improper refrigerant charge.
Defective high or low pressure control.
Cycling on internal overload.
Defective expansion valve.
Poor air distribution.
High discharge pressure.
Leaking discharge valves in compressor. Check thermostat, check heat anticipator setting.
Check subcooling, verify superheat.
Check high or low pressure switch.
Possible tight bearings – see above.
Check TXV and superheat.
Check ductwork for recirculation.
See above – high discharge pressure.
See above – high suction pressure.