General Troubleshooting Chart - Rheem PNL-*AZ Series Installation Instructions Manual

15.6 GENERAL TROUBLE SHOOTING CHART
WARNING
Disconnect all power to unit before servicing. Contactor may break only one side. Failure to shut off power can
cause electrical shock resulting in personal injury or death.
SYMPTOM
Unit will not run
Outdoor fan runs, compressor
doesn't
Insufficient cooling
Compressor short cycles
Registers sweat
High head-low vapor pressures
High head-high or normal vapor
pressure - Cooling mode
Low head-high vapor pressures
Low vapor pressure - cool
compressor - iced indoor coil
High vapor pressure
Fluctuating head & vapor
pressures
Gurgle or pulsing noise at
expansion device or liquid line
POSSIBLE CAUSE
• Power off or loose electrical connection
• Thermostat out of calibration-set too high
• Defective contactor
• Blown fuses / tripped breaker
• Transformer defective
• High pressure control open (if provided) or defrost
control lockout due to 3 high pressure control trips.
• Low pressure control open (if provided) or defrost
control lockout due to 3 low pressure control trips.
• Run or start capacitor defective
• Start relay defective
• Loose connection
• Compressor stuck, grounded or open motor winding,
open internal overload.
• Low voltage condition
• Improperly sized unit
• Improper indoor airflow
• Incorrect refrigerant charge
• Air, non-condensibles or moisture in system
• Incorrect voltage
• Defective overload protector
• Refrigerant undercharge
• Low indoor airflow
• Restriction in liquid line, expansion device or filter drier
• Flowcheck piston size too small
• Incorrect capillary tubes
• Dirty outdoor coil
• Refrigerant overcharge
• Outdoor fan not running
• Air or non-condensibles in system
• Flowcheck piston size too large
• Defective Compressor valves
• Incorrect capillary tubes
• Low indoor airflow
• Operating below 65°F outdoors
• Moisture in system
• Low refrigerant charge
• Excessive load
• Defective compressor
• TEV hunting
• Air or non-condensibles in system
• Air or non-condensibles in system
REMEDY
• Check for correct voltage at contactor in condensing unit
• Reset
• Check for 24 volts at contactor coil - replace if contacts are
open
• Replace fuses / reset breaker
• Check wiring-replace transformer
• The high pressure control opens at 610 PSIG. Check for blocked
coils, failed fan or blower motor, wiring issues, or defective high
pressure control. See section 8.6 to reset defrost control.
• The low pressure control opens at 25 PSIG. Check for low
charge, blocked coils, wiring issues, or defective low pressure
control. See section 8.6 to reset defrost control.
• Replace
• Replace
• Check for correct voltage at compressor -
check & tighten all connections
• Wait at least 2 hours for overload to reset.
If still open, replace the compressor.
• Add start kit components
• Recalculate load
• Check - should be approximately 400 CFM per ton.
• Charge per procedure attached to unit service panel
• Recover refrigerant, evacuate & recharge, add filter drier
• At compressor terminals, voltage must be ± 10% of
nameplate marking when unit is operating.
• Replace - check for correct voltage
• Add refrigerant
• Increase speed of blower or reduce restriction - replace air
filter
• Remove or replace defective component
• Change to correct size piston
• Change coil assembly
• Clean coil
• Correct system charge
• Repair or replace
• Recover refrigerant, evacuate & recharge
• Change to correct size piston
• Replace compressor
• Replace coil assembly
• Increase speed of blower or reduce restriction - replace air
filter
• Add Low Ambient Kit
• Recover refrigerant - evacuate & recharge - add filter drier
• Repair leak, evacuate, & recharge.
• Recheck load calculation
• Replace
• Check TEV bulb clamp - check air distribution on coil - replace
TEV
• Recover refrigerant, evacuate & recharge
• Recover refrigerant, evacuate & recharge
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