Thermocouple Probe

Remove thermocouple leads from the temperature

 

 

control board and measure the millivolt output of these

 

 

leads. Refer to chart on Page 25 for proper readings.

 

 

If the thermocouple probe checks good, replace

 

 

temperature control.

 

Flame Monitor

Check for 220 VAC at terminal #1. If no voltage is

 

 

present, trace wiring back to temperature control.

 

 

Check for 220 VAC output at terminal #8. NOTE:

 

 

There is a delay of up to 2 seconds for 220 VAC

 

 

output at terminal #8. If there is no voltage output at

 

 

terminal #8, check the reset button. Replace control

 

 

as needed.

 

Relay, Main Burner

Check for 220 VAC at relay coil, if no voltage is

 

 

present, trace wiring back to flame monitor. Check for

 

 

120 VAC to relay contacts. If no voltage is present,

 

 

trace wiring back to power supply. Check to ensure

 

 

contacts are closing

 

Valve, Temperature

Replace relay as needed. Check for 120 VAC at

 

Regulation

valve, if no voltage is present, trace wiring back to

 

 

relay. If voltage is present, listen for valve to open and

 

 

close. Check for opens or shorts in coil. Replace as

 

 

needed.

Main Flame will not

Flame Monitor

(There should be a visible main flame at this time.) To

stay lit

 

check for flame monitor operation, connect a digital

 

 

voltmeter (capable of measuring D.C. microamperes)

 

 

between the flame sensor and terminal #15 on the

 

 

flame monitor. The flame monitor requires a minimum

 

 

of 4 micro amp. D.C. for proof of flame. If these

 

 

readings are not achieved, replace sensor assembly.

 

 

Also check for any type of damage to flame sensor

 

 

wire and connections. If the reading is above the

 

 

minimum required, and the flame monitor will not

 

 

supply 220 VAC to the relay coil, replace the flame

 

 

monitor.

Intermittent heating

As Follows

Both the main fan motor and burner blower motor are

 

 

equipped with thermal protection and will cease to

 

 

operate if overheating occurs. This can cause the

 

 

units to cycle on and off intermittently. This may be

 

 

caused by improper ventilation. Also most of the

 

 

problems listed under "oven will not heat" can cause

 

 

intermittent failure. See page 13 for test lights.

Impinger I – 1400 Series Advantage Service Manual – Dom & Int’l

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Lincoln 1400 Series service manual