Fdo Heavy Duty Oven Control - Garland M series Operation Manual

ADJUSTMENTS Continued

FDO Heavy Duty Oven Control

The model FDO oven thermostat is a precision-made
instrument, carefully set at the factory to accurately control
oven temperatures from 150° to 500°F, (66° to 260°C). All
adjustments are accessible from the front of the appliance
after moving the dial. To remove the dial, grasp the outer
edges and pull straight out.
By-Pass Adjustment
The Robertshaw FDO snap/throttle thermostat requires that
the by-pass flame be properly adjusted. To adjust proceed as
follows:
Indicator Mark
Calibration
Plate
Dial
Stop
MODEL
FDO
1. Ensure pilot flame is lit and adjusted.
2. Turn oven temperature control to 200°F, (93°C), and allow
the oven to heat for three minutes.
3. Turn, the oven temperature control to the lowest
position, then turn slowly counter-clockwise until the
audible "click" is heard.
4. Making sure the oven temperature control dial is not
disturbed, turn the by-pass flame adjusting screw
clockwise to decrease, or counter-clockwise to increase
the flame on the burner to the lowest possible stable
flame. When properly adjusted, the by-pass flames will
cover the entire length of the burner.
Part # 1382680 Rev 3 (05/10/11)
Calibration Instructions
Field calibration is seldom necessary and should not
be resorted to unless experience with cooking results
undoubtedly indicate that the control is not maintaining
the temperature for which the dial is set. To check oven
temperatures when calibrating, use only a reliable mercury
thermometer, or preferably an oven pyrometer. To check
calibration, proceed as follows:
1. Place the thermocouple of the test instrument or reliable
mercury thermometer in the center of the oven.
2. Turn the oven temperature control knob to 400°F, (204°C),
and allow the oven to cycle at least three times.
3. Continue to monitor the oven temperature, recording
the readings at 5 minute intervals until three successive
By-pass Flame
Adjuster
readings are within 5°F, (2°C), of each other.
Calibration
Lock Screws
If the temperature does not read within 15°F, (8°C), of the dial
setting, recalibrate as follows.
1. Remove the oven temperature control dial, making sure
the setting is not disturbed.
2. Hold the calibration plate, (located directly behind the
control dial), and loosen the two calibration lock screws
until the plate can be rotated independently of the
control.
3. Turn the calibration plate until the temperature indicated
on the plate corresponds with the reading on the test
instrument. Hold the plate in place and tighten the
screws firmly.
4. Repeat step 3 in the previous section, checking the
temperature to ensure the adjustment has been made
properly.
5. Replace the temperature control dial.
NOTE: If adjustment of the calibration plate is prevented by
the position of the lock screws, the screws can be moved to
other holes that have been tapped for them.
Page 19