Middleby Marshall PS200 series - Manual (Page 41)

40
Diagnostic Error Messages
The controller runs background tests during normal operation. If any problems occur during the tests, an
error message flashes in the display. A listing of these diagnostic error messages is shown below.
Flashes on the display (alter-
nating with the temperature)
indicating that the internal di-
agnostic test has failed.
The oven temperature has
not reached 200°F/93°C
within 15 minutes of startup.
On gas ovens, this is usually
a result of the burner not light-
ing.
Caused by an open in the
thermocouple circuit.
Polarity of the thermocouple
leads is reversed.
1. Turn the Blower Switch (HEAT Switch for PS536 ovens with the two-
switch configuration) OFF for 2 minutes.
2. Turn the Blower Switch (or HEAT Switch, as per Step 1) ON.
3. If necessary, repeat Steps 1 and 2 up to two additional times.
4. If the problem does not clear after 3 attempts, replace the controller.
1. Turn the Blower Switch (HEAT Switch for PS536 ovens with the two-
switch configuration) OFF for 2 minutes.
2. Turn the Blower Switch (or HEAT Switch, as per Step 1) ON.
3. If the problem does not clear, contact the Middleby Technical Ser-
vice Department for assistance.
1. Check that the thermocouple leads are properly connected to Ter-
minals 7 & 8 of the temperature controller.
2. Check the continuity of the thermocouple at room temperature. You
should measure 9-20 Ohms of resistance.
3. If the reading was outside the correct range, the thermocouple has
an open. Remove and replace the thermocouple.
If the reading was inside the correct range, contact the Middleby
Technical Service Department for assistance.
1. Check the polarity of the thermocouple leads. The red wire (-) should
be attached to Terminal 7 on the temperature controller. The white
wire (+) should be attached to Terminal 8.
2. If the polarity connections are incorrect, connect the thermocouple
properly.
If the polarity connections are correct, replace the thermocouple.
Page 8 of 10
SECTION 3 - SERVICING COMPONENTS
Appendix - Instructions for Service Kit 47321 - Digital Temperature Controller Kit, 2/02