Rheem 018J*Z, Installation Instructions Manual

23

SYMPTOM

POSSIBLE CAUSE

REMEDY

Unit will not run

• Power off or loose electrical connection

• Check for correct voltage at contactor in condensing unit

• Thermostat out of calibration-set too high

• Reset

• Defective contactor

• Check for 24 volts at contactor coil - replace if contacts are

open

• Blown fuses / tripped breaker

• Replace fuses / reset breaker

• Transformer defective

• Check wiring-replace transformer

• High pressure control open (if provided)

• Reset-also see high head pressure remedy-The high pressure

control opens at 450 PSIG

Outdoor fan runs, compressor

• Run or start capacitor defective

• Replace

doesn’t

• Start relay defective

• Replace

• Loose connection

• Check for correct voltage at compressor -

check & tighten all connections

• Compressor stuck, grounded or open motor winding,

• Wait at least 2 hours for overload to reset.

open internal overload.

If still open, replace the compressor.

• Low voltage condition

• Add start kit components

Insufficient cooling

• Improperly sized unit

• Recalculate load

• Improper indoor airflow

• Check - should be approximately 400 CFM per ton.

• Incorrect refrigerant charge

• Charge per procedure attached to unit service panel

• Air, non-condensibles or moisture in system

• Recover refrigerant, evacuate & recharge, add filter drier

Compressor short cycles

• Incorrect voltage

• At compressor terminals, voltage must be ± 10% of

nameplate marking when unit is operating.

• Defective overload protector

• Replace - check for correct voltage

• Refrigerant undercharge

• Add refrigerant

Registers sweat

• Low indoor airflow

• Increase speed of blower or reduce restriction - replace air

filter

High head-low vapor pressures

• Restriction in liquid line, expansion device or filter drier

• Remove or replace defective component

• Flowcheck piston size too small

• Change to correct size piston

• Incorrect capillary tubes

• Change coil assembly

High head-high or normal vapor

• Dirty outdoor coil

• Clean coil

pressure - Cooling mode

• Refrigerant overcharge

• Correct system charge

• Outdoor fan not running

• Repair or replace

• Air or non-condensibles in system

• Recover refrigerant, evacuate & recharge

Low head-high vapor pressures

• Flowcheck piston size too large

• Change to correct size piston

• Defective Compressor valves

• Replace compressor

• Incorrect capillary tubes

• Replace coil assembly

Low vapor - cool compressor -

• Low indoor airflow

• Increase speed of blower or reduce restriction - replace air

iced indoor coil

filter

• Operating below 65°F outdoors

• Add Low Ambient Kit

• Moisture in system

• Recover refrigerant - evacuate & recharge - add filter drier

High vapor pressure

• Excessive load

• Recheck load calculation

• Defective compressor

• Replace

Fluctuating head & vapor

•

pressures

• Air or non-condensibles in system

• Recover refrigerant, evacuate & recharge

Gurgle or pulsing noise at

• Air or non-condensibles in system

• Recover refrigerant, evacuate & recharge

expansion device or liquid line

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.

TROUBLE SHOOTING CHART

WARNING

!

• TEV hunting

Check TEV bulb clamp - check air distribution on coil - replace
TEV