Lincoln Impringer Conveyor Oven 1200 - Manual (Page 39)

Impinger I -–1000 Series Service Manual - International 39
TROUBLESHOOTING GUIDE 1000 & 1200 SERIES / ELECTRIC OVENS
SYMPTOM POSSIBLE CAUSE EVALUATION
Incoming Power Supply Check breakers/Reset if required/ Call Power Co. if
needed.
(Export Ovens) 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.
Oven Fan Fuse(s) Check and/or Replace
Fuse Holder Check and/or Replace
Fan Switch Check continuity between switch terminals.
Main Relay Check continuity to 120 VAC coil. Check for power
to the relay coil (120 VAC). Check for 208/220/240
VAC to relay terminals. Visually check for contact
pull-in
Fan Motor Check for opens, shorts, or grounds. WITH POWER
OFF: Turn Fan Blade to check for locked rotor.
Oven fan will not run
NOTE:
Capacitor Check for opens, shorts, or grounds.
No Main Fan Cool
Down Cool Down Thermostat Check cool down thermostat (thermostat closes at
160°F and opens at 140°F). Check for power (120
VAC) at cool down thermostat. With cool down
thermostat pre-heated, check for continuity. If
switch is open, replace.
Main Fan Relay Check for power to main fan relay. Visually check
for contact pull in. No control box cooling
Axial Cooling Fan WITH POWER OFF: turn the fan blade to 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.
Main Oven Fan Check if main oven fan is operating. If not, refer to
"Oven fan will not run."
Heat Switch Check for continuity between switch terminals with
switch on. Replace if defective.
Air Pressure Switch Check for 120 VAC on both sides of switch. If
voltage present on one side only, check for air tube
blockage, adjust air switch. If above fails, replace
air pressure switch.
Hi Limit Thermostat Terminals are normally closed. If open, reset and
test oven for proper operation. If thermostat will not
hold for maximum oven temperature, and oven is
not exceeding temperature dial setting, replace
thermostat (rated at 190°F).
Hi Limit Thermostat
(Model 1032) Terminals are normally closed. If open, reset and
test oven for proper operation. If thermostat will not
hold for maximum oven temperature, and oven is
not exceeding temperature dial setting. Replace the
thermostat. Check for proper location of sensing
bulb in its spring holder. If hi-limit is still tripping,
replace (rated for 368°C).
3 Amp Temperature Control
Fuse Check and/or Replace
Oven will not heat
NOTE:
Fuseholder Check and/or replace.