Heat Controller BG-123A, BG-81A, BG-101A service manual Complaint Cause Remedy

COMPLAINT	CAUSE	REMEDY
Fan motor will not run.	No power	Check voltage at outlet. Correct if none.
	Power supply cord	Check voltage to rotary switch. If none, check
		power supply cord. Replace cord if circuit is open.
	Rotary switch	Check switch continuity. Refer to wiring diagram
		for terminal identification. Replace switch if
		defective.
	Wire disconnected or	Connect wire. Refer to wiring diagram for terminal
	connection loose	identification. Repair or replace loose terminal.
	Capacitor (Discharge	Test capacitor.
	capacitor before testing.)	Replace if not within ±10% of manufacturer's
		rating. Replace if shorted, open, or damaged.
	Will not rotate	Fan blade hitting shroud or blower wheel hitting
		scroll. Realign assembly.
		Units using slinger ring condenser fans must
		have 1/4 to 5/16 inch clearance to the base. If it is
		hitting the base, shim up the bottom of the fan
		motor with mounting screw(s).
		Check fan motor bearings; if motor shaft will not
		rotate, replace the motor.
Fan motor runs	Revolves on overload.	Check voltage. See limits on page 27. If not within
intermittently		limits, call an electrician.
		Test capacitor.
		Check bearings. Does the fan blade rotate freely?
		If not, replace fan motor.
		Pay attention to any change from high speed to
		low speed. If the speed does not change, replace
		the motor.
Fan motor noise.	Grommets	Check grommets; if worn or missing, replace them.
	Fan	If cracked, out of balance, or partially missing,
		replace it.
	Turbo fan	If cracked, out of balance, or partially missing,
		replace it.
	Loose set screw	Tighten it.
	Worn bearings	If knocking sounds continue when running or
		loose, replace the motor. If the motor hums or
		noise appears to be internal while running,
		replace motor.

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