If arcing does not occur:

Check circuitry; refer to dryer Main Panel Wiring Diagram and dryer Solenoid Junction Box Wiring Diagram.

Check transformer

Check spark igniter in burner

Refer to the ML-460 Service Manual (ADC Part No. 450023) for more information on the burner controller module and burner start-up.

Retest

5b) To check the electrical actuation of the motorized gas valve:

Shut the main gas valve to the dryer.

Open the disconnect block on TB1-64, for circuit testing. With control voltage “ON” apply a 100 VAC a line to TB1-64 “output.” THE LOWER MOTORIZED GAS VALVE “V3” SHOULD OPEN. ONCE THE “V3” IS OPEN THE SECOND MOTORIZED GAS VALVE “V2” SHOULD OPEN.

NOTE: REMOVING THE VOLTAGE AT ANY TIME WILL CLOSE THE VALVES INSTANTLY.

If valves operate properly, close disconnect on TB1-64.

If the valves do not open correctly;

Check circuitry; refer to dryer Main Panel Wiring Diagram and MLG-464 Solenoid Junction Box Wiring Diagram.

Check motorized valves

Refer to Section VI, Part D, Gas Burner and Ignition System on page 37 thru page 45.

Retest

6b) To verify that MS4 AUX is operational:

Start a drying cycle, MS4 contactor should pull in, and start the LINT FAN and LINT SCREEN motors. Simultaneously MS4 AUZ1 should close, enabling MS8 Coil (Burner Fan Motor) to be asserted by burner controller module. Does MS4 pull in?

If MS4 pulls in go to paragraph #7b

If MS4 “DOES NOT” pull in;

Check that PLC (Programmable Logic Controller) OUTPUT 3 L.E.D. (light emitting diode) is “ON”

Check that fuse #14 L.E.D. (light emitting diode) “IS NOT” lit

68

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American Dryer Corp MLG-460 manual