Troubleshooting Guide; Gas Ovens - Lincoln 1400 Series Service Manual

SYMPTOM POSSIBLE CAUSE
Oven fan will not run Incoming Power Supply
NOTE:
(Export Ovens)
Oven Fan Fuse
Control Fuse
Fuse Holder
Fan Switch
Main Relay
Fan Motor
Capacitor
No control box Main Fan Relay
cooling
No automatic control Incoming Power Supply
box cooling
Cooling Fan Thermostat
Axial Cooling Fan
Control box cooling Cooling Fan Thermostat
fan continues to run
Oven will not heat Gas Supply
Model 1450-1451
Manual Gas Shut-off Valve
Main Oven Fan
For 1456, 1457, Centrifugal Switch
1475, 1476 See
Page 14.
Transformer, 24 VAC
Burner Blower Motor
Impinger I – 1400 Series Advantage Service Manual – Dom & Int'l

TROUBLESHOOTING GUIDE

GAS OVENS

IMPINGER ADVANTAGE SERIES
EVALUATION
Check breakers, reset if required. Call Power Co. if
needed
For some export ovens, there is a control circuit step-
down transformer. This transformer steps down
supply voltage to 120 VAC. If main fan will not run,
the secondary of this transformer must be checked
for 120 VAC output. Check specific oven model
schematic for circuit location.
Check and/or Replace
Check and/or Replace
Check and/or Replace
Check continuity between switch terminals
Check continuity to 120 VAC coil. Check for power to
relay coil (120VAC). Check for supply voltage to
relay contacts. Visually check for contact pull-in.
Check for opens, shorts, or ground. WITH POWER
OFF: Turn Fan Blade to check for locked rotor.
Check for opens, shorts, or grounds.
Check for power to main fan relay. Visually check for
contact pull-in. Axial Cooling Fan. Check for power
(120 VAC or 240 VAC, check specific model) to
cooling fan. If voltage is present at the fan motor and
the fan does not run, replace fan assembly.
Check breakers/Reset if needed. Check for incoming
power at cooling fan thermostat.
Check cooling fan thermostat (thermostat closes at
120°F and opens at 100°F). With cooling fan
thermostat pre-heated, check for continuity. If switch
is open, replace.
WITH POWER OFF: check for locked rotor. Check
for proper voltage to the cooling fan, if present and
fan does not run, replace the fan.
See "Cooling Fan Thermostat" (NOTE: Thermostat
will remain closed if control box temperature
exceeds 120°F)
Check for adequate gas supply to oven
Check to see that manual shut-off valve is open
Check if main oven fan is operating. If not, refer to
"Oven fan will not run" on page 11.
Check for 120 VAC on both sides of (Main Fan)
switch. If voltage present on one side only, and motor
is running, replace motor.
Check for 120 VAC to primary of transformer. Check
for 24 VAC from secondary of transformer. If there is
primary voltage, but no secondary voltage, replace
transformer.
Check for 120 VAC supply to burner blower motor. If
120 VAC is present and motor does not run, replace
motor. WITH POWER OFF: turn blower wheel to
check for locked rotor.
11