Electrical Fault Isolation Guide; 60-Minute Timer; Timer Contacts; Timer Motor - Market Forge Industries ST-10 Owner's Manual

SECTION 5. TROUBLE-SHOOTING
FAILURE
Will not operate in either CONSTANT STEAM or 60-MINUTE
TIMER position.
Operating in CONSTANT STEAM position but not in 60-MINUTE
TIMER position.
Operating in 60-MINUTE TIMER position but not in CONSTANT
STEAM position.
Steam solenoid valve fails to open with indicator light on.
Indicator light OFF with steam solenoid open.
With indicator light ON and steam solenoid valve OPEN, timer
dial fails to turn.
Buzzer fails to SOUND at end of 60-MINUTE TIMER mode.
Steam flows continuously from boiler drain line.

5.4.4 60-MINUTE TIMER

5.4.4.1 TIMER CONTACTS

Defective timer contacts will result in failure of ei-
ther cooker compartment to operate. When this
occurs, remove the control panel (see Subsection
6.3.4), and proceed as follows:
1. Turn off power to the cooker at external cir-
cuit breaker.
2. Disconnect all five wires from timer termi-
nals (see Figure 5-1).
3. Connect an ohmmeter between terminals 1
and 3.
4. Rotate timer dial beyond the "0-Minute" point
(any setting) to obtain a reading of zero ohms
on the ohmmeter. If zero ohm reading can-
not be obtained, timer contacts are defective
and the timer must be replaced.

ELECTRICAL FAULT ISOLATION GUIDE

Table 5-2
FAULT LOCATION
a. Incoming power.
b. Timer.
c. Door interlock switch.
d. Wiring.
a. 60-Minute timer.
b. Wiring.
a. 60-Minute timer.
b. Wiring.
a. Solenoid valve coil.
b. Wiring.
a. Indicator light.
b. Wiring.
a. Compartment thermostatic switch.
b. Constant steam position.
c.

Timer motor.

d. Wiring.
a. 60-Minute timer.
b. Buzzer.
c. Wiring.
a. Thermostatic switch.
b. Cold water solenoid valve.
c. Wiring.
5. Move ohmmeter leads to terminals 1 and 4.
6. Rotate timer dial to "0-Minute" position (an
audible click indicates correct position). If
zero ohm reading cannot be obtained, the
timer is defective and must be replaced.
7. Remove ohmmeter and replace all five leads
on timer terminals as shown in Figure 5-1.
5.4.4.2 TIMER MOTOR
A defective timer motor will cause continuous
operation in the TIME mode, with the timer dial
failing to return to the "0-Minute" position. Since
thermostatic switch failure can cause the same
symptom, fault must first be isolated to the timer
by testing the thermostat (see Subsection 5.4.8).
To confirm timer motor condition, proceed as fol-
lows:Ful te nemplint, nem pra? Palis cont.
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