Lincoln 1133-000-A - Manual (Page 14)

Impinger II – Advantage Digital Service Manual - Domestic 14
activate, replace the mercury contactor. Also
check each contactor for high voltage input and
output.
Heating element(s) Check the Amp draw on each power leg for
proper load. Check the specification plate for
rating information. If the amp draw is high or low,
check the individual elements for opens, shorts
and proper resistance.
WITH POWER OFF: To check resistance of the
elements, remove all leads from the elements
and use a digital multimeter.
The element resistance is should be as follows:
208V – 27 ohms
240V – 36 ohms
Replace heating elements as needed.
Oven heats with switch off Mercury contactor The mercury contactor has probably failed in the
closed position. If there is no voltage to the
operating coil, but there is high voltage at the
contactor output, replace the mercury contactor.
Intermittent heating Thermal/overload of motor The main fan motor is equipped with internal
thermal protection and will cease to operate if
overheating occurs. As the motor overheats and
then cools, this will cause the oven to cycle on
and off intermittently. Improper ventilation or lack
of preventive maintenance may cause this. Also,
most of the problems listed under “Oven will not
heat” can cause intermittent failure.
Conveyor will not run Power supply Check circuit breakers, reset if required. Check
power plug to be sure it is firmly in receptacle.
Measure incoming power, call power co. if
needed.
Fuse, 10 Amp Check, replace if necessary.
Fuse holder Check, replace if necessary.
Hi-limit thermostat, control box Check for voltage on both sides of switch.
Terminals are normally closed. If open, reset and
test oven for proper operation. If thermostat will
not hold, and control box temperature is not
exceeding 140
°F (60°C), replace thermostat.
Power switch Check continuity between switch terminals.
Replace switch as needed.
Control transformer Check for supply voltage to the primary of the
control transformer. If no voltage is present, trace
wiring back to the oven power relay. If voltage is
present, check for 24 VAC at the transformer
secondary. If there is primary voltage but no
secondary voltage, replace control transformer.
Conveyor motor Check for supply voltage to the conveyor motor.
If no voltage is present, trace wiring back to the
primary of the control transformer. If voltage is
present and the motor will not run, check the
motor windings for opens or shorts.
WITH POWER OFF: Check the motor windings
as follows:
Grey to black - 240
Ω approx.
Grey to tan - 240
Ω approx.
Tan to black - 480
Ω approx.
If any of the above fails, replace conveyor motor.
Capacitor, conveyor motor Check for shorts or grounds. Replace capacitor
as needed.
WARNING: Capacitor has a stored charge,