Page 34
Troubleshooting Guide
MD24 and MD30
5-11
#824820 - Revision A - December, 2013
COMPONENT TEST
PROCEDURE LETTER
H
THERMAL CUT-OUT TEST:
1. Disconnect power supply cord.
2. Open drawer and keep it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. A continuity check across thermal cut-out terminals should indicate a closed
circuit unless temperature of the thermal cut-out reaches approximately
293°F(145°C). An open thermal cut-out indicates overheating of oven,
exchange oven thermal cut-out and check inside of oven cavity and for
improper setting of cooking time or operation of control unit. Check for
restricted air flow through vent holes of oven cavity, especially cooling fan and
air guide.
5. Reconnect all leads removed from components during testing.
6. Reassemble unit.
7. Reconnect power supply cord.
8. Run unit and check all functions.
If the thermal cut-out indicates an open circuit at room temperature, replace
thermal cut-out.
I
SECONDARY INTERLOCK SWITCH TEST:
1. Disconnect power supply cord.
2. Open drawer and keep it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Isolate switch and connect ohmmeter to the common (COM.) and normally
open (NO) terminal of switch. Meter should indicate an open circuit with
drawer open and a closed circuit with drawer closed. If improper operation is
indicated, replace secondary interlock switch.
5. Reconnect all leads removed from components during testing.
6. Reassemble unit.
7. Reconnect power supply cord.
8. Run oven and check all functions.
J
STOP SWITCH TEST:
1. Disconnect power supply cord.
2. Open drawer and keep it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Isolate switch and connect ohmmeter to common (COM.) and normally open
(NO) terminal of switch. Meter should indicate an open circuit with drawer
open and a closed circuit with drawer closed. If improper operation is indicat-
ed, replace stop switch.
5. Reconnect all leads removed from components during testing.
6. Reassemble unit.
7. Reconnect power supply cord.
8. Run oven and check all functions.
NOTE:
If the stop switch contacts fail in the open position and door is closed,
cooling fan motor, stirrer motor and oven light will be activated by RY1.
