Cornelius MJ31-4 PB, MJ32-4 PB Cont, Troubleshooting Guide, Problem, Probable Cause, Remedy

Troubleshooting Guide

Problem	Probable Cause	Remedy
TWO OR MORE PUMPS	VRB Board mounting screw	Check the corresponding VRB board
OPERATE WHEN ONLY	insulator is missing or	to the valve that is dispensing in
ONE BUTTON IS PUSHED.	improperly installed.	error. Where the screw mounts the
(Cont.)		transistor to the bracket, be sure that
		the spacer bushing is present and the
		screw is not over tightened. Screw
		contact with the bracket will cause a
		short and the firing of the valve when
		other valves are energized.
WITH POWER PRESENT	Refrigeration shut off switch	Refrigeration shut off switch is
DISPENSER WILL NOT	is in the off position.	located on the top of the dispenser.
COOL		This switch will disable the
		compressor and condenser fan motor.
		Be sure the switch is in the on
		position.
Drink temperature should be	Depleted ice bank (not	Remove rear bonnet covering the
35-45°F	applicable after period of	refrigeration deck. CAUTION should
°	heavy usage.)	be observed when working in this
2-7 C		area as the dispenser is energized and
		operational. Check to see if the
		compressor is running . If so allow
		the system to recover (approximately
		1 hour).
WITH POWER PRESENT	Loose or broken wire	Check the wire connections at the
COMPRESSOR WILL NOT	connections.	compressor. Be sure they are tightly
RUN.		secured.
(Compressor shell is cold to
touch.)	Defective compressor start	Check the compressor start relay.
	component.	Replace as required.
	Ice bank control not connected	Check the ice bank control
	or defective.	connections. To test, place jumper
		between the 2 leads. If the
		compressor starts ,the ice bank
		control is defective.
COMPRESSOR RUNS BUT	Low refrigerant charge.	Contact a refrigeration service
NO COOLING IS TAKING		technician. They will check for leaks
PLACE.		(sign of oil at joints and fitting) and
		will recharge if necessary.
	Refrigerant restriction.	Refrigeration technician will examine
		the system for, kinks in lines,
		restrictions, etc. Heat exchanger may
		need to be replaced.

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