Friedrich 2008, 2009 service manual Heat Pump Troubleshooting, Incorrect wiring

HEAT PUMP TROUBLESHOOTING

Problem	Possible Cause	Action
	Incorrect wiring	Refer to applicable wiring diagram
	Defective solenoid coil	Check for continuity of coil
		Block condenser coil & switch unit to cooling.
Unit cools when	Reversing valve fails to shift	Allow pressure to build up in system, then
		switch to heating. If valve fails to shift, replace
heat is called for
		valve.
	Inoperative system switch or defrost	Check for continuity. Replace defective
	thremostat or outdoor thermistor or
		component.
	electronic board

Problem	Possible Cause	Action
	Heating capillary tube partially	Check for partially starved outer coil. Replace
	restricted	heating capillary tube
		Switch unit several times from heating to
Heating	Check valve leaking internally	cooling. Check temperature rise across
insufficient		coil. Refer to specifi cation sheet for correct
		temperature rise
	Reversing valve failing to shift	Deenergize solenoid coil, raise head pressure,
		energize solenoid to break loose. If valve fails
	completely; bypassing hot gas
		to make complete shift, replace valve.

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