Service manual

M411429 39
Section 3 Troubleshooting
To reduce the risk of electric shock, fire, explosion, serious injury or death:
• Disconnect electric power to the tumbler before servicing.
• Close gas shut-off valve to gas tumbler before servicing.
• Close steam valve to steam tumbler before servicing.
• Never start the tumbler with any guards/panels removed.
• Whenever ground wires are removed during servicing, these ground wires must be
reconnected to ensure that the tumbler is properly grounded.
W002
WARNING
© Copyright, Alliance Laundry Systems LLC – DO NOT COPY or TRANSMIT
42. MM MODELS: NO HEAT WITH CYCLE SELECTED, UNIT RUNNING AND CALLING FOR
HEAT
120 Volt/60 Hertz/1 Phase and 208-240 Volt/60 Hertz/1 Phase Gas and Steam Nonreversing
480 Volt/60 Hertz/3 Phase and 208-240 Volt/60 Hertz/3 Phase Steam Reversing and Nonreversing
Step Problem If No, then
1 Is there voltage to COM terminal of the micro control?
If yes, continue to next step.
Correct wiring between door switch and micro control.
2 Is there voltage to the N.O. terminal of the micro control?
If yes, continue to next step for gas models, to step 20 for
steam models.
Replace micro.
3 Is there voltage to the input of the stove high limit? If yes,
continue to next step.
Correct wiring between stove high limit and micro
control.
4 Is there voltage to the output of the stove high limit? If yes,
continue to next step.
Check for proper airflow. If airflow is good, replace
stove high limit.
5 Is there voltage to the N.O. terminal of the airflow switch?
If yes, continue to next step.
Correct wiring between airflow switch and stove high
limit.
6 Is there voltage at COM of the airflow switch? If yes,
continue to next step.
Check for proper airflow and function of airflow switch.
Replace airflow switch if necessary.
7 Is there voltage to the input of the cabinet limit? If yes,
continue to next step.
Correct wiring to between cabinet limit and airflow
switch.
8 Is there voltage to the output of the cabinet limit? If yes,
continue to next step.
Replace cabinet limit.
9 Is there voltage to terminal 1 of CR2? If yes, continue to
next step.
Correct wiring between CR2 and cabinet limit.
10 Is there voltage to terminal 3 of the CR2 If yes, continue to
next step.
Continue with step 16.
11 Is there voltage to L1 of I.E.I. board? If yes, continue to
next step.
Correct wiring between I.E.I. board and CR2.
12 Is there voltage across gas valve coils? If yes, continue to
next step.
Check wiring. Replace I.E.I. board if necessary.
13 Is the igniter sparking? If yes, continue to next step. Check resistance of High Voltage lead (5k and 20k).
Replace if necessary.
14 Is there gas flow through the valve? If yes, continue to step
22.
Check for proper gas pressure. Replace gas valve if
necessary.
15 Is there voltage across the coil of CR2. If yes, continue to
next step.
Replace CR2.
16 Is there 120 VAC on terminal 3 of motor? If yes, correct
wiring between CR2 and motor. Continue to step 22.
Replace motor.
17 Is there voltage across the coil of the steam valve? If yes,
continue to next step.
Correct wiring to steam valve.
18 Does the unit heat? If yes, continue to next step. Check for proper steam supply. Replace steam valve if
necessary.
19 Unit operational.