Lincoln 1131-000-A Oven User Manual


 
Impinger II – Advantage Digital Service Manual - Domestic
10
voltage output at the oven control, check the read-
out on the control. If the control reads “PROBE
FAIL”, this indicates that the thermocouple has
failed or become disconnected from the oven
control.
Thermocouple Check to be sure that the thermocouple is
securely connected to the oven control. If the
thermocouple is connected to the oven control,
and the control indicates “PROBE FAIL”,
disconnect the thermocouple from the oven
control and measure the resistance of the
thermocouple. The thermocouple should read
approx. 11Ω. If these readings are not achieved,
replace the thermocouple. If these readings are
correct, proceed.
Oven control If the thermocouple checks good, but the oven
control display indicates that there is a
thermocouple failure, replace the oven control. If
the oven control indicates a temperature reading
but the oven will not heat, proceed.
Thermocouple WITH POWER ON AND THERMOCOUPLE
ATTACHED TO THE OVEN CONTROL: Measure
the DC millivolt output of the thermocouple. Refer
to the thermocouple chart (located in the
“Removal” section of the manual) for proper
millivolt readings. If these readings are not
achieved, replace thermocouple.
Oven control If the thermocouple checks good, but there is no
120VAC output to the temperature regulation
valve, replace the oven control. If there is 120VAC
output to the temperature regulation valve,
proceed.
Temperature regulation valve Check for 120VAC supplied to temperature
regulation valve. If voltage is present, listen for
valve to open and close. Also check for opens or
shorts in the operating coil. Replace temperature
regulation valve as needed.
Intermittent heating Thermal/overload of main fan
and burner blower motors
The main fan motor and burner blower motor are
equipped with internal thermal protection and will
cease to operate if overheating occurs. As the
motors overheat and then cool, this will cause the
heating system to cycle on and off intermittently.
Improper ventilation or lack of preventive
maintenance may cause this problem. Also, most
of the problems listed under “Oven will not heat”
can cause intermittent failure.
Conveyor will not run Power supply Check for incoming voltage at line 1 to neutral.
There should be a reading of 120VAC. If not
present, check circuit breakers.
Fuse, 10 Amp Check, replace if necessary.
Fuse holder Check, replace if necessary.
Hi-limit thermostat, control box Check for voltage on both sides of switch.
Terminals are normally closed. If open, reset and
test oven for proper operation. If thermostat will
not hold, and control box temperature is not
exceeding 140°F (60°C), replace thermostat.
Power switch Check continuity between switch terminals.
Replace switch as needed.
Control transformer Check for 120 VAC supply to the primary of the
control transformer. If no voltage is present, trace