System Troubleshooting - Whirlpool WGPH45 AM Installation Instructions Manual

Symptom
High head—low suction
High head—high or normal
suction
Low head—high suction
Unit will not run.
Condenser fan runs;
compressor does not run.
Low suction—Cool
compressor, iced evaporator
coil
Compressor short cycles
Registers sweat
High suction pressure
Insufficient cooling
Evaporator coil freezing or
frosting
10

System Troubleshooting

Possible Cause
■ Restriction in liquid line or flowrator
■
Dirty condenser coil
■ Overcharged
■ Condenser fan not running
■ Incorrect flowrator
■ Defective compressor valves
■ Flowrator not seating properly
■
Power off or loose electrical connection
■ Thermostat out of calibration; set too
high
■
Defective contactor
■
Blown fuses or tripped circuit breaker
■ Transformer defective
■ High or low pressure control (optional)
open
■ Compressor overload contacts open
■
Loose connection
■
Compressor stuck
■
Grounded or open winding
■
Open internal overload
■
Low voltage connection
■ Capacitor weak, open or shorted
■ Low indoor airflow
■ Defective overload protector
■ Unit cycling on low pressure control
■ High pressure switch cuts out
■ Low airflow
■
Excessive load
■
Defective compressor
■ Reversing valve not seating properly.
■
Improperly sized unit
■ Improper airflow
■ Incorrect refrigerant charge.
■ Incorrect voltage
■ Low airflow
■ Low refrigerant charge
■
Operating unit in cooling mode below
65ºF (18ºC) outdoor temperature
Remedy
■ Remove or replace with proper size flowrator.
■
Clean coil.
■ Correct system charge.
■ Repair or replace condenser fan.
■ Replace with correct flowrator.
■ Replace compressor.
■ Check for debris under flowrator or deformed flowrator.
Remove debris or replace flowrator.
■
Check for unit voltage at contactor in unit.
■ Reset thermostat.
■
Check for 24 volts at contactor coil. Replace if contacts
are open.
■
Replace fuse or reset circuit breaker. Check wiring.
Replace transformer.
■ Reset high pressure control or check unit charge.
High pressure control opens at 610 psig, and low
pressure control opens at 22 psig.
■ Replace compressor.
NOTE: Wait at least 2 hours for overload to reset.
■
Check for unit voltage at compressor.
■
Check and tighten all connections.
■
Wait at least 2 hours for overload to reset. If still open,
replace the compressor.
■ At compressor terminals, voltage must be within 10%
of nameplate volts when unit is operating.
■ Check capacitor. Replace if defective.
■ Increase speed of blower or reduce restriction.
■ Replace air filters.
■ Replace overload protector. Check for correct voltage.
■ Check refrigerant charge and/or airflow.
■ Check airflow (indoor and outdoor)
■ Increase speed of blower or reduce restriction.
■ Replace air filters.
■
Recheck load calculation
■
Replace compressor.
■ Replace reversing valve.
■
Recalculate load.
■ Check airflow—should be approximately 400 CFM per
ton.
■ Charge per procedure attached to unit service panel.
■ At compressor terminals, voltage must be within 10%
of nameplate volts when unit is operating.
■ Check airflow—should be approximately 400 CFM per
ton.
■
Properly charge unit.
■
Install or check low ambient control—should be open
below 65ºF (18ºC) outdoor temperature.