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 won’t

 

 

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

The main fan motor and burner blower motor are

 

and burner blower motors

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

 

 

wiring back to the oven power relay. If voltage is

 

 

present, check for 24 VAC at the transformer

 

 

secondary. If there is primary voltage but no

 

 

secondary voltage, replace control transformer.

 

Conveyor motor

Check for 120 VAC supply to the conveyor motor at

 

 

wire #14 to neutral. If no voltage is present, trace

 

 

wiring back to the primary of the control transformer.

 

 

If voltage is present and the motor will not run, check

 

 

the motor windings for opens or shorts.

 

 

WITH POWER OFF: Check the motor windings as

 

 

follows:

 

 

Grey to black - 38Ω approx.

 

 

Grey to blue - 38Ω approx.

 

 

Blue to black - 75Ω approx.

 

 

If any of the above fails, replace conveyor motor.

 

Capacitor, conveyor motor

Check for shorts or grounds. Replace capacitor as

14

Impinger II – Advantage Digital Express Service Manual - Domestic

Page 14
Image 14
Lincoln 1162-080-A, 1132-080-A, 1131-08H-A, 1132-08H-A, 1116-080-A1, 1130-08H-A, 1133-08H-A With Power on and Thermocouple