Friedrich RAC-SVC-06 service manual Heat / Cool Room AIR Conditioners Troubleshooting Tips

HEAT / COOL ROOM AIR CONDITIONERS: TROUBLESHOOTING TIPS

Problem	Possible Cause	Action
		Disconnect power to unit. Remove resistor
	Heat anticipator (resistor) shorted	from t-stat bulb block. Plus in unit & allow to
	(on applicable models)	operate. Feel resistor for heat. If not heat,
Room temperature		replace resistor
uneven	Wide differential - partial loss of	Replace t-stat & check
(Heating cycle)	t-stat bulb charge
		Refer to appropriate wiring diagram. Resistor
	Incorrect wiring	is energized during "ON" cycle of compressor
		or fan.

Problem	Possible Cause	Action
	Incorrect wiring	Refer to appropriate wiring diagram
	Defrost control timer motor not	Check for voltage at "TM" & "TM1" on timer. If
	advancing (applicable models)	no voltage, replace control
	Defrost control out of calibration	If outside coil temperature is 25F or below, &
		preselected time limit has elapsed, replace
	(applicable models)
Unit will not defrost		defrost control
		If contacts remain closed between terminals
	Defrost control contacts stuck	"2" & "3" of the defrost control after
		preselected time interval has passed, replace
		control
	Defrost control bulb removed from	Reinstall & be assured that good bulb to coil
	or not making good coil contact	contact is made

Problem	Possible Cause	Action
	Exhaust or fresh air door open	Check if operating properly. Instruct customer
		on proper use of control
	Dirty fi lter	Clean as recommended in Owner's Manual
		Check heat rise across coil. If unit operates
	Unit undersized	effi ciently, check if insulation can be added
		to attic or walls. If insulation is adequate,
Does not heat		recommend additional unit or larger one
		T-stat should close at 38°F. Check continuity of
adequately	Outdoor t-stat open (applicable
		control. If temperature is below 38°F, replace
	models)
		control
	Heater hi-limit control cycling on &	Check for adequate fan air across heater.
		Check control for open at 160°F & close at
	off
		150°F
	Shorted supplementary heater	Ohmmeter check, approx. 32-35 ohms
	Incorrect wiring	Check applicable wiring diagram

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