Friedrich 2003 service manual Problem Possible Cause To Correct

PROBLEM	POSSIBLE CAUSE	TO CORRECT
	Dirty filter.	Clean as recommended in Owner’s Manual.
Evaporator coil	Restricted air flow.	Check for dirty or obstructed coil - clean as re-
		quired.
freezes up.	Inoperative thermostat.	Test for shorted thermostat or stuck contacts.
	Short of refrigerant.	De-ice coil and check for leak.
	Inoperative fan motor.	Test fan motor and replace if inoperative.
	Partially restricted capillary.	De-ice coil. Check temperature differential across
		coil. Touch test coil return bends for same tempera-
		ture. Test for low running current.

PROBLEM	POSSIBLE CAUSE	TO CORRECT:
	Excessive heat load.	Unit undersized. Test cooling performance of unit.
Compressor runs		Replace with larger unit.
	Restriction in line.	Check for partially iced coil. Check temperature split
continually.
		across coil.
	Refrigerant leak.	Check for oil at silver soldered connections. Check
Does not cycle off.		for partially iced coil. Check split across coil. Check
		for low running amperage.
	Thermostat contacts stuck	Check operation of thermostat. Replace if contacts
		remain closed.
	Thermostat incorrectly wired.	Refer to appropriate wiring diagram.

PROBLEM	POSSIBLE CAUSE	TO CORRECT:
	Thermostat contacts stuck.	Replace thermostat.
Thermostat does not	Thermostat set at coldest point.	Turn to higher temperature setting to see if the unit
turn unit off.		cycles off.
	Incorrect wiring.	Refer to appropriate wiring diagram.
	Unit undersized for area to be cooled.	Refer to Sizing Chart.

PROBLEM	POSSIBLE CAUSE	TO CORRECT
	Overload inoperative. Opens too soon.	Check operation of unit. Replace overload if
		system operation is satisfactory.
	Compressor attempts to start before	Allow a minimum of two (2) minutes for pressures
	system pressures are equalized.	to equalize before attempting to restart. Instruct
		customer of waiting period.
Compressor attempts	Low or fluctuating voltage.	Check voltage with unit operating. Check for other
		appliances on circuit. Air conditioner should be on
to start, or runs for		separate circuit for proper voltage, and be fused
short periods only.		separately.
Cycles on overload.	Incorrect wiring.	Refer to appropriate wiring diagram.
	Shorted or incorrect capacitor.	Check by substituting a known good capacitor of
		correct rating.
	Restricted or low air flow through	Check for proper fan speed or blocked condenser.
	condenser coil.	Check for kinked discharge line or restricted condenser.
	Compressor running abnormally hot.	Check amperage.

PROBLEM	POSSIBLE CAUSE	TO CORRECT
Thermostat does not	Loss of charge in thermostat bulb.	Place jumper across thermostat terminals to check
		if unit operates. If unit operates, replace thermostat.
turn unit on.
	Loose or broken parts in thermostat.	Check as above.
	Incorrect wiring.	Refer to appropriate wiring diagram.

37