Lincoln 1400 Series Service Manual page 12

Centrifugal Switch of Burner
Blower Motor
Ignition Control
No Pilot
Pilot Shut-off Valve
Pilot Tube
Pilot Orifice
Burner Igniter
Pilot flame but no Ignition Control
main flame
Main Orifice
Temperature Control
(Electronic)
12
Check for 24 VAC output from secondary of
transformer. If voltage is present, check for 24 VAC
at pin 6 and ground on ignition control. If the burner
blower motor is running and there is no voltage at pin
6 and the ground on the ignition control, replace the
burner blower motor.
Check for 24 VAC supply to the ignition control at pin
6 and the ground. If voltage is present, check for 24
VAC across pin #3 and ground (pilot valve). NOTE:
The Honeywell ignition control has a 30 sec. pre-
purge (Time Delay) built in. If voltage is not present,
replace electronic control package. If the pilot valve
is energized, check to see that the high voltage
igniter circuit is also energized. To check, disconnect
the igniter lead from the ignition control. Place female
terminal of igniter lead approximately 1/8" from
terminal post on ignition control. Spark should jump
the 1/8" gap. If no spark is present, replace ignition
control. NOTE: control will try for ignition for 15
seconds only.
If the ignition control is supplied with 24 VAC and the
pilot valve (internal to valve assembly) and igniter
circuits are energized, visually check for pilot flame.
This may be done by opening the small inspection
door on the end of the burner, or by opening the
main oven door and looking under the lower finger
housings on the right side of the oven. If no pilot
flame is visible, check pilot shut-off valve.
Check to see that pilot shut-off valve is open (shut-off
valve is located between valve assembly and
burner).
Check for gas pressure at pilot tube. Disconnect pilot
tube at burner and connect manometer to pilot tube.
If no gas pressure is present, check for blockage in
pilot tube or pilot shut-off valve. If these are clear,
and there is gas supplied to the oven, replace the
gas valve.
If there is gas pressure at the pilot tube, check the
pilot orifice for obstructions. Replace as needed.
Check the burner igniter head for any obstructions,
also check for frayed or broken wire, (spark gap .100
in. 2.5 mm). If there is visible damage, replace igniter
assembly.
If there is a pilot flame, check for 24 VAC across
terminals #1 and the ground (main valve). If there is
no voltage present, replace the ignition control.
NOTE: The Honeywell ignition control has a 15-sec.
lockout built in. If pilot flame is not proven, turn off
switch, wait 30 sec. and restart. If power is supplied
to terminal #1 but there is no main flame, verify that
the main valve (internal to valve assembly) has
opened. Connect a manometer to the manifold gas
pressure tap located on the back of the valve
assembly. If no gas is present, replace valve
assembly. Check for temperature control set above
300°F.
Check for blockage of main orifice. If there is no
blockage to the main orifice, check the temperature
control.
Check for 120 VAC across L1 and L2 on temperature
control board.
Impinger I – 1400 Series Advantage Service Manual - Dom & Int'l