Merco Savory 86002 service manual Troubleshooting Guide, Symptom Possible Cause Evaluation

TROUBLESHOOTING GUIDE

SYMPTOM	POSSIBLE CAUSE	EVALUATION
Holding Cabinet will	Incoming Power Supply	Verify power cord is secured firmly in receptacle.
not heat		Measure the incoming voltage. Check circuit
		breakers. Reset if required. Call power company
		if needed.
	Power Switch	Check continuity between switch terminals.
		Replace switch as needed.
Unit doesn’t reach	Thermocouple	Check for continuity in circuit.
desired temperature
	Heat Element	Compare cavity temperature with display reading.
		Insert temperature probe into center of cavity.
		Acceptable temperature variation is +/- 20° from
		display reading.
		Check for loose connection.
		Check the Amp draw on each element for proper
		load. Check page 2 for rating information. If the
		amp draw is high or low, check the individual
		elements for opens, shorts and proper resistance.
		WITH POWER OFF: To check resistance of the
		elements, remove all leads from the elements and
		use a digital multimeter.
		The element resistance should be as follows:
		120V – 87 ohms
		Replace heating element (shelf) as needed.
		Check thermostat (common wire). Please note
		that if thermostat is bad, both circuits will be bad.
Temperature is too	Thermocouple	Check for incorrectly wired thermocouple.
high		Thermocouple wire polarities are reversed.
	Heat Element	Compare cavity temperature with display reading.
		Insert temperature probe into center of cavity.
		Acceptable temperature variation is +/- 20° from
		display reading.
		Check for loose connection.
		Check the Amp draw on each element for proper
		load. Check page 2 for rating information. If the
		amp draw is high or low, check the individual
		elements for opens, shorts and proper resistance.
		WITH POWER OFF: To check resistance of the
		elements, remove all leads from the elements and
		use a digital multimeter.
		The element resistance should be as follows:
		120V – 87 ohms
		Replace heating element (shelf) as needed.

6 Holding Cabinet – Service Manual