26
OVEN THERMOSTAT CALIBRATION CHECK
124 SERIES
NOTE:
The oven temperature should be
checked or recalibrated with oven hot.
NOTE:
See ―Adjustment of Bypass (Minimum
Burner) Flame‖ above before recalibrating this
thermostat.
HOT CHECK METHOD
1. Place the reliable thermometer in center of
oven.
2. Set dial (6) at 350 degrees F.
3. Wait until temperature rises and remains
constant.
4. If dial does not agree with thermometer
readings, slip off Dial (6) and push out
insert (7).
5. Replace dial, turn to 350 degree mark.
6. Hold dial firmly, insert screwdriver through
center of dial and push calibration stem (2)
inward.
DO NOT TURN THIS STEM.
7. While holding calibration stem (2) in firmly
with screwdriver, turn dial until it is set at the
actual oven temperature as shown by your
test instrument or thermometer. Release
pressure on calibration stem. Replace dial
insert.
OPERATIONAL DIFFICULTIES &
PROBABLE CAUSES
OVEN PILOT BURNER GOES OUT:
1. Gas shut off.
2. Poor draft in flue snuffs out flame.
3. Too much draft pulls flame away from
thermocouple.
4. Pilot flame too low.
5. Thermocouple defective.
6. Thermocouple connection on safety pilot
loose.
7. Pilot orifice dirty.
8. Pilot Safety valve defective.
9. Gas leak at pilot orifice fitting.
10. Restricted or plugged vent on gas pressure
regulator.
OVEN BURNER FAILS TO COME ON
(PILOT ON):
1. Burner valve off.
2. Burner orifice plugged.
3. Thermostat out of calibration.
4. Minimum flame adjustment closed and ther-
mostat setting too low.
OVEN TEMPERATURE HIGHER THAN
DIAL SETTING:
1. Oven thermostat out of calibration.
2. Minimum flame too high. (Do not lower under
1/8‖).
3. Broken capillary tube on the thermostat
4. Dirt under thermostat valve seat.
