Carrier 48TJD008-014, 48TJE008-014, 48TJF008-012 Ð Cooling Service Troubleshooting

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.

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