Table 20 Ð Cooling Service Troubleshooting

PROBLEM

CAUSE

REMEDY

Compressor and

Power failure.

Call power company.

condenser fan

Fuse blown or circuit breaker tripped.

Replace fuse or reset circuit breaker.

will not start.

Defective thermostat, contactor, transformer, or control

Replace component.

 

 

relay.

 

 

Insufficient line voltage.

Determine cause and correct.

 

Incorrect or faulty wiring.

Check wiring diagram and rewire correctly.

 

Thermostat setting too high.

Lower thermostat setting below room temperature.

Compressor will not start

Faulty wiring or loose connections in compressor circuit.

Check wiring and repair or replace.

but condenser fan runs.

 

 

Compressor motor burned out, seized, or internal

Determine cause. Replace compressor.

 

overload open.

 

 

Defective run/start capacitor, overload, or start relay.

Determine cause and replace.

 

One leg of 3-phase power dead.

Replace fuse or reset circuit breaker.

 

 

Determine cause.

Compressor cycles

Refrigerant overcharge or undercharge.

Recover refrigerant, evacuate system, and recharge

(other than normally

 

to nameplate.

satisfying thermostat).

 

 

Defective compressor.

Replace and determine cause.

 

 

Insufficient line voltage.

Determine cause and correct.

 

Blocked condenser.

Determine cause and correct.

 

Defective run/start capacitor, overload, or start relay.

Determine cause and replace.

 

Defective thermostat.

Replace thermostat.

 

Faulty condenser-fan motor or capacitor.

Replace.

 

Restriction in refrigerant system.

Locate restriction and remove.

Compressor makes

Compressor rotating in wrong direction.

Reverse the 3-phase power leads as described

excessive noise

 

on page 23.

(48TJ014 scroll only)

 

 

Compressor operates

Dirty air ®lter.

Replace ®lter.

continuously.

 

 

Unit undersized for load.

Decrease load or increase unit size.

 

 

Thermostat set too low.

Reset thermostat.

 

Low refrigerant charge.

Locate leak, repair, and recharge.

 

Leaking valves in compressor.

Replace compressor.

 

Air in system.

Recover refrigerant, evacuate system, and recharge.

 

Condenser coil dirty or restricted.

Clean coil or remove restriction.

Excessive head pressure.

Dirty air ®lter.

Replace ®lter.

 

Dirty condenser coil.

Clean coil.

 

Refrigerant overcharged.

Remove excess refrigerant.

 

Air in system.

Recover refrigerant, evacuate system, and recharge.

 

Condenser air restricted or air short-cycling.

Determine cause and correct.

Head pressure too low.

Low refrigerant charge.

Check for leaks, repair, and recharge.

 

Compressor valves leaking.

Replace compressor.

 

Restriction in liquid tube.

Remove restriction.

Excessive suction

High heat load.

Check for source and eliminate.

pressure.

 

 

Compressor valves leaking.

Replace compressor.

 

 

Refrigerant overcharged.

Recover excess refrigerant.

Suction pressure too low.

Dirty air ®lter.

Replace ®lter.

 

Low refrigerant charge.

Check for leaks, repair, and recharge.

 

Metering device or low side restricted.

Remove source of restriction.

 

Insufficient evaporator air¯ow.

Increase air quantity. Check ®lter and replace if

 

 

necessary.

 

Temperature too low in conditioned area.

Reset thermostat.

 

Field-installed ®lter drier restricted.

Replace.

Compressor no. 2

Unit in economizer mode.

Proper operation; no remedy necessary.

will not run.

 

 

34

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Carrier 48TJD008-014, 48TJE008-014, 48TJF008-012 installation instructions Cooling Service Troubleshooting
Page 33 Page 35

48TJF008-012, 48TJD008-014, 48TJE008-014 specifications

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