Troubleshooting Guide 1000 & 1200 / Gas Ovens - Lincoln Impinger Conveyor Oven Series 1200 Service Manual

TROUBLESHOOTING GUIDE 1000 & 1200 / GAS OVENS
SYMPTOM
Oven fan will not run
NOTE:
No Main Fan Cool
Down
No Control Box
Cooling(For ovens
equipped with Control
Box Cooling Fan)
NOTE:
No automatic control
box cooling (For ovens
equipped with control
box cooling fan)
Control box cooling fan
continues to run
Transformer, 24 VAC
26
POSSIBLE CAUSE
Incoming Power Supply
(Export Ovens)
Oven Fan Fuse(s)
Fuse Holder
Fan Switch
Main Relay
Fan Motor
Capacitor
Cool Down Thermostat
Main Fan Relay
(Export Ovens)
Axial Cooling Fan
Incoming Power Supply
Cooling Fan Thermostat
Axial Cooling Fan
Cooling Fan Thermostat
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.
Manual Gas Shut-off Valve
Fan Switch
Main Oven Fan
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 continuity between switch terminals.
Check continuity to 120 VAC coil. Check for power
to relay coil (120 VAC). Check for 208/240 VAC to
relay terminals. Visually check for contact pull-in.
Check for opens, shorts, or grounds. WITH
POWER OFF: Turn Fan Blade to check for locked
rotor.
Check for opens, shorts, or grounds.
Check cool down thermostat (thermostat closes at
160° F and opens at 140° F). Check for power (120
VAC) at cool down thermostat. With the cool down
thermostat pre-heated, check for continuity. If
switch is open, replace.
Check for power to Main Fan Relay. Visually check
for contact pull in.
(For ovens equipped with a control circuit step-
down transformer, the supply voltage for the
cooling fan is 240 VAC.)
WITH POWER OFF: check for locked rotor. Check
for power (120 VAC) to cooling fan. If 120 VAC is
present at the fan motor and the fan does not run,
replace fan assembly.
Check breakers/Reset if needed. Check for
incoming power (120 VAC)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.
Check for 120 VAC to cooling fan, if present and
fan does not run, replace fan.
See "Cooling Fan Thermostat"
Check for adequate gas supply to oven.
Check to see that manual shut-off valve is open.
Check to see that fan switch is "on".
Check if main oven fan is operating. If not, refer to
"Oven fan will not run". Page 26.
Impinger I -–1000 Series Service Manual - International