Lincoln 1450 Manuel D’Utilisation

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Impinger I – 1450 Series Service Manual - Domestic 
the display, replace oven control. If there is a read-out 
on the control, set the control to maximum temperature 
(see Installation operations manual for temperature 
adjustment). With the control set at maximum 
temperature, check for 120VAC at the temperature 
regulation valve. If there is voltage at the temperature 
regulation valve, proceed to “Temperature regulation 
valve” for next check. If there is no voltage at the 
temperature regulation valve, trace wiring back to the 
oven control. If there is no voltage output at the oven 
control, check the read-out on the oven 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. 
11
Ω. 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 the 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 
Incoming power supply 
Check circuit breaker, reset if required. Check power 
plug to be sure it is firmly in receptacle. Measure 
incoming power, call power co. if needed. 
 
Fuse, 10 Amp 
Check, replace if necessary. 
 
Fuse holder 
Check, replace if necessary. 
 
Switch, oven power 
Check for 120VAC supply to switch. If no voltage is 
present, trace wiring back to fuse holder. Check 
continuity between switch terminals. Replace switch as 
needed.