Garland 40 Series Technical Reference Manual - page 43
Part # GCTRM Rev 3 (12/10/09)
Page 43
NOTE: A replacement thermostat will come with the by-pass
in the closed position.
CALIBRATION
SCREW
BY-PASS
ADJUSTMENT
SCREW
Calibrating The BJWA Thermostat
This control is a precision component, it is carefully calibrated
at the factory. Re-calibration should not be undertaken until
the by-pass flame has been adjusted and the operating gas
pressure has been confirmed.
To check the temperature when re-calibrating, use an
appropriate temperature reading meter. Position of the
instrument/thermocouple should be in the geometric center
of the oven. For a griddle, use a disc type thermocouple
placed in the center of each zone. Thereshouldbeno
productsintheovenoronthegriddle
If the dial has a removable metal insert, proceed as follows:
1. Remove the dial and push out the insert.
2. Replace the dial and turn to the 350° mark.
3. After the burner has been on about 15 minutes, check the
temperature.
4. Continue to check the temperature at 5 minute intervals
until 2 successive reading are with in 5° of each other.
Thecontrolshouldbere-calibratedifyourreading
isnotwithin±20°Fofthedialsetting(350°F) .If
re-calibrationisrequired,theadditionalstepsthat
needtobetakenareasfollows:
5. Hold the dial firmly, insert a screwdriver through the
center of the dial and push the calibration stem. Do Not
turn this stem.
6. While holding the calibration stem firmly with the
screwdriver, turn the dial until it is set at the actual
temperature as shown on your meter. Release the
pressure on the calibration stem. Replace the dial inset.
7. Set the dial at 400°F mark. Check the temperature again
as indicated in step 3 and 4 above. If the temperature is
not with in ±20° of the dial setting (400°F), the control
should be replaced.
If the dial does not have a removable insert or the dial has a
“D” type stem, use the following procedure to re-calibrate.
1. Set the dial to the 350°F mark.
2. After the burner has been on about 15 minutes, check the
temperature.
3. Continue to check the temperature at 5 minute intervals
until 2 successive readings are within 5°F of each other.
Thecontrolshouldre-calibratedifyourreading
isnotwithin±20°ofthedialsetting(350°F) .Ifre-
calibrationisrequired,theadditionalstepsthat
areneedtobetakenareasfollows:
4. Remove the dial assembly or the complete “D” type stem.
5. Push the calibration stem inward with a screw driver,
while holding the calibration stem firmly in, turn the
stem clockwise to obtain a lower temperature or counter-
clockwise for a higher temperature. Each mark on the
retainer represents 25°F. Replace the dial assembly or “D”
type stem with dial.
6. Set the dial at 400°F mark. Check the temperature again
as indicated in step 3 and 4 above. If the temperature is
not with in ±20° of the dial setting (400°F), the control
should be replaced.