Heat Controller BHD-501-D, BHD-651-D, BHD-301-D service manual Troubleshooting Guide

4. TROUBLESHOOTING GUIDE

CONDITION	CAUSE	REMEDY
1. Dehumidifier does not start. (Both	No power	Check power supply at outlet.
compressor and fan motor do not		Correct if none.
operate.)
	Poor plug contact at outlet.	Install plug properly or replace it.
	Bucket is full.	If Auto Shut Off lights, empty the bucket
		and replace properly.
	Humidity control is at Off position	Turn the humidity control switch toward
		Max.
	Wire disconnected or loose	Connect wire. Refer to wiring diagram for
		terminal identification. Repair or replace
		loose terminal.
	Capacitor.	Test capacitor.
	(Discharge capacitor before testing.)	Replace if not within ±10% of
		manufacturer's rating. Replace if shorted,
		open, or damaged.
2. Motor runs but compressor does not	Voltage (115V ± 10%)	It must be between 103.5V and 126.5V. If
run.		not within limits, call an electrician
	Wiring	Check the wire connections; If loose,
		repair or replace the terminal. If the wires
		are disconnected, refer to wiring diagram
		for identification, and replace the wires.
		Check the wire connections; If not
		according to the wiring diagram, correct
		the connections.
	Rotary switch	Check for continuity, refer to the wiring
		diagram for terminal identification. Replace
		the switch if the circuit is open.
	Defrost control	The Defrost Control senses frost build-up
		on the evaporator coil and automatically
		shuts off the compressor. The fan
		continues to run, drawing air across the
		coil, and melting the frost. When the coil is
		defrosted, the compressor automatically
		restarts, and dehumidifying resumes.
	Capacitor	Check the capacitor.
	(Discharge capacitor before servicing.)	Replace if not within ±10% of
		manufacturer's rating. Replace if shorted,
		open, or damaged.
	Compressor	Check the compressor for open circuit or
		ground. If open or grounded, replace the
		compressor.
	Overload protector (OLP)	Check the compressor OLP if externally
		mounted. Replace if open. (If the
		compressor temperature is high, remove
		OLP, cool, and retest.)
3. Does not defrost control.	Defrost control is defective.	Check defrost control, replace it.
4. Insufficient dehumidification	Low relative humidity	Turn dehumidifier off.
	Poor air circulation	Move dehumidifier to obtain free and
		unobstructed air circulation.
	H/E clogged with dust and dirt	Clean evaporator and/or condenser assembly
	Air filter is dirty.	Clean it.
	Motor is not operating.	Check Motor, repair or replace it.

— 17—