Market Forge Industries 3500 Incoming Power, Electric Inspection, Minute Timer  Timer Contacts

TROUBLE-SHOOTING

The electrical trouble-shooting procedures that follow require access to components and terminals of the electrical control panel shown in Fig. 6 on page 21. Electrical controls are reached by removing screws that fasten the control panel to the frame. The panel may be pulled forward for testing while interconnect- ed to the cooker circuits or disconnected at the pin connection for complete removal and repair.

INCOMING POWER:

Before trouble-shooting any of the electrical parts or assemblies, verify that power is being supplied to the cooker. Incoming power is connected at the boiler (or direct-connected steam) control box located in the base cabinet. With power connected to the cooker, an AC volt-meter is used to measure 120 volts across L1 and L2. If 120 volts is present, and the cooker will not operate, the fault lies within the electrical circuits of the cooker.

ELECTRIC INSPECTION:

The first step in any electrical trouble-shooting pro- cedure is a thorough physical inspection of all wiring connections.

WARNING:

Before removing control panel or checking connec- tions and wiring, be sure that the circuit breaker for in- coming power is OFF. When power is supplied, all ex- posed terminals of the control panel carry 120 volts.

Check all wiring connections by hand to assure that both ends of all connection points are tightly secured. Use a screwdriver to tighten connection points. If nec- essary, visually inspect all quick-disconnect terminals for evidence of corrosion. Terminals in this condition should be separated, cleaned with emery cloth until shiny, and tightly reconnected.

60 MINUTE TIMER:

TIMER CONTACTS:

Defective timer contacts will result in failure of either cooker compartment to operate. When this occurs, remove the control panel and proceed as follows:

1.Turn off power to the cooker at external circuit breaker.

2.Disconnect all five wires from timer terminals. (see Fig. 2, page 11).

ELECTRICAL FAULT ISOLATION GUIDE

	FAILURE	FAULT LOCATION
1.	Will not operate in either constant steam or 60 minute timer.	A. Incoming power.
		B. Timer.
		C. Door interlock switch/relay.
		D. Wiring.
2.	Operating in constant steam position, but not in 60 minute timer.	A. 60 minute timer.
		B. Wiring.
3.	Operating in 60 minute timer position, but not in constant steam.	A. Timer.
		B. Wiring.
4.	Steam solenoid valve fails to open with indicator light on.	A. Solenoid valve coil.
		B. Wiring.
5.	Indicator light off with steam solenoid valve open.	A. Indicator light.
		B. Wiring.
6.	With indicator light off steam solenoid valve open, timer dial fails to turn.	A. Compartment thermostatic switch.
		B. Constant steam position.
		C. Timer motor.
		D. Wiring.
7.	Buzzer fails to sound at end of 60 minute timer mode.	A. 60 minute timer contacts.
		B. Buzzer.
		C. Wiring.
8.	Steam flows continuously form boiler drain line.	A. Thermostatic switch.
		B. Cold water solenoid valve.
		C. Wiring.

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