Vulcan-Hart Snorkel SG-22 Installation Manual page 18

TROUBLE-SHOOTING - SERVICE (Continued)
Problem: 2. The blower is "ON" (with auxiliary
fan switch de-energized) but no heat.
Procedure:
Turn the thermostat knob to about the
400°F. position. If the oven signal light is turned "ON",
follow step A; if not, follow step B.
STEP A — Oven indicator light is "ON". This is an in-
dication that the door switch, and the thermostat are
functioning properly. The problem can then be related
to the load control switch or the solenoid.
Turn the load control knob to "HI" position.
Check the voltage between terminals L 1 & L 2 of the
load control switch.
If no voltage, check for bad connection or faulty lead
to the switch.
If 120 volts, check the voltage across H 1 & H 2 ter-
minals of the switch.
If no voltage, the switch is defective.
If 120 volts, check for defective solenoid or faulty
connection between the load control and the solenoid.
STEP B — Oven indicator light does not come "On".
This is an indication that the door switch, load control
or thermostat could be defective. (Check for a bad
connection between the master switch and the
thermostat, defective thermostat or bad connection
between the normally open contact of the door swit-
ches and leads going to the solenoids.
Problem: 3. The oven heats up properly when
empty, but as soon as the food is put in it, the
temperature drops and the oven never
recovers.
Procedure:
Meals containing excessive moisture can
cause the temperature to drop. Also, a cause of
temperature drop is excess load.
Problem: 4. The oven temperature keeps
increasing beyond the setting of the
thermostat.
Procedure: If the thermostat indicator light cycles on
and off, check for defective solenoid. If the thermostat
light remains "On" check for defective thermostat
contacts.
Problem: 5 The motor turns off and
automatically comes back "ON" after a few
minutes.
Procedure: The internal thermal protector of the motor
is sensing a high temperature which is caused by:
A—High current. Check for clockwise rotation of the
shaft, for any binding on the shaft or the blower wheel
(the wheel should be rotated freely by a hand touch). If
none of the above, the motor may be defective.
B—High ambient. Check for hot air leakage from inside
the oven to the back through the light or motor
housings. Check to see if hot air is being blown on the
motor from the adjacent equipment.
Check for proper ventilation in the area.
208-240 volt units note: Sometimes the over current
affects the circuit breaker (15 amp breaker) before it
does the thermal protector; and the circuit breaker
keeps tripping to the "OFF" position.
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