Lincoln 1400 Series Service Manual page 16

Flame will not stay on Flame Sensor
Ignition Control
No Pilot Pilot Orifice
Pilot flame, but burner Flame Sensor
will not stay ignited
Power Supply
Ignition Control
Indicator light is on, Gas Control Relay
but no main
flame(Model 1456-
1457)
Temperature Control
Thermocouple Probe
Solenoid Valve
Indicator light is on, Temperature Control
but no main flame
(1474-1475-1476)
16
To check for flame sensor operation, connect a digital
multimeter (capable of measuring D.C. micro amps)
between the flame sensor wire and Ignition Control.
Sensor current from sensor control is 3 micro amps
minimum. If these readings are not achieved replace
igniter/sensor assembly. Also check for any type of
damage to flame sensor wire and connections.
If there is sufficient flame sensor current, but the
burner will not remain ignited, check the reset button
on ignition control. If all above are okay, replace
ignition control.
If all above are operating properly, but there is no pilot
flame, check for any obstructions in pilot orifice.
(There should be a visible pilot flame at this time.) To
check for flame sensor operation, connect a digital
multimeter (capable of measuring D.C. micro
amperes) between the flame sensor wire and the
ignition control. NOTE: this is a current measurement
and the meter must be connected in series. Proper
current readings should be minimum of 3 micro AMP.
D.C. If these readings are not achieved, replace
igniter/sensor assembly. Also check for any type of
damage to flame sensor wire and connections.
If there is sufficient micro-amp current, but the flame
will not stay lit, check for proper polarity of the input
power supply.
If there is sufficient flame sensor current, but the
burner will not remain ignited, check reset button on
ignition control, if all above are okay, replace ignition
control.
Check for 220 VAC to relay coil. If no voltage is
present, trace wiring back to ignition control. If voltage
is present, check to insure contacts are closing.
Check for 120 VAC across L1 and L2 on temperature
control board. If no voltage is present, retrace wiring
back to power supply. Turn the temperature
adjustment knob to the maximum temperature
position and check for 120 VAC at the load terminal to
neutral. If 120 VAC is not present, proceed as
follows: If 120 VAC is present and unit is not heating,
see "Solenoid Valve."
Remove thermocouple leads from the temperature
control board and measure the millivolt output of these
leads. Refer to chart in page 25 for proper readings.
If the thermocouple probe checks good, then the
problem is usually with the temperature control board.
If output voltage is present at temperature control
board, check for voltage at solenoid valve. If voltage
is present, listen for valve to open and close. Also
check for opens, shorts in coil. Replace as needed.
Check for 120 VAC across L1 and L2 on temperature
control board. If no voltage is present, retrace wiring
back to power supply. Turn the temperature
adjustment knob to the maximum temperature
position and check for 220 VAC at the
to neutral. If 220 VAC is not present, proceed as
follows: If 220 VAC is present, and unit is not heating,
see "Flame Monitor". Check for 220 VAC at terminal
"COM" on temperature control board. If no voltage is
present, trace wiring back to ignition control.
Impinger I – 1400 Series Advantage Service Manual - Dom & Int'l
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