Friedrich R-410A service manual Troubleshooting, Problem, Possible Cause, Possible Solution

TROUBLESHOOTING

Problem	Possible Cause	Possible Solution
	Compressor attempts to start	Allow a minimum of 3 minutes to allow pressures
	before system pressures are
		to equalize before attempting to start.
	equalized.
		Check voltage with unit operating. Check for
	Low or fluctuating voltage.	other appliances on the circuit. Unit should be on
		separate circuit for proper voltage, and be fused
Compressor
		separately
attempts to
	Incorrect wiring	Connect per appropriate wiring diagram
start, or runs for
	Shorted or incorrect capacitor	Replace capacitor
short periods
only. Cycles on
	Restricted or low air flow through
overload.		Check motor fan blade.
	condenser coil
	Compressor running abnormally	Check for refrigerant restriction, blocked airflow,
		loose wires at compressor terminals and fan
	hot
		motor capacitor voltage.
	Overload opens too soon.	Change compressor if all other corrections above
		are normal.

Problem	Possible Cause	Possible Solution
	Thermostat contacts not closing.	Check continuity of thermostat at coldest setting. If
		compressor runs, replace thermostat.
	Low voltage supply.	Check for nameplate voltage. Provide proper
		voltage.
Compressor does	Switch (On-Off) inoperative.	Test for continuity.
not start - fan	Defective capacitor.	Test with analyzer, replace if needed.
motor runs.	Compressor internal overload	Check voltage at compressor terminals. If voltage
	open.	is satisfactory, replace compressor.
	Solid state relay open.	Replace relay.
	Open or shorted compressor	Check windings for continuity and resistance. If
	windings.	open, replace compressor.

Problem	Possible Cause	Possible Solution
	Thermostat open or inoperative.	Set to coldest position. Test thermostat and
		replace if necessary.
	Dirty air filter.	Clean as recommended in Owner’s Manual.
Does not cool, or	Dirty or plugged condenser or	Clean coils.
	evaporator coil.
cools only slightly.
	Poor air circulation in area being	Adjust air louvers. Check application. Check for
		dirty filter or evap coil. Check fan motor. Correct as
	cooled.
		needed.
	Low capacity - undercharge.	Check for leak and make necessary repairs.
	Compressor not pumping properly.	Replace compressor.

NOTE: If Inside Coil Freezes Up

Your Friedrich Hazardgard is designed not to freeze with outdoor temperatures as low as 45°F (7°C). If the indoor coil should ice over while cooling, set the thermostat to the warmest position until the ice on the coil is gone. Setting the thermostat to a slightly warmer position will probably keep ice from forming on the coil. A dirty filter will contribute to icing.

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