![background image](http://html1.mh-extra.com/html/garland/master-mst42r/master-mst42r_installation-operating-and-service-manual_564189025.webp)
Part # 4519069 (07/24/09)
Page 25
1. Place the thermocouple of the test instrument in the
center of the oven.
2. Light the oven, set the thermostat to 400°F (204°C) and
wait 15 minutes for the oven temperature to stabilize.
3. Check the temperature at 5 minute intervals until three
successive readings are within ±5°F (±3°C) of each other.
4. If the temperature is not within ±20°F (±8°C) of the
thermostat dial setting, refer to Figure 10 to recalibrate
using this procedure.
Figure 10 – Oven thermostat
450 500
5
50
15
0
300
2
50
3
00
35
0
40
0
Calibration
Lock Screws
By-pass Flame
Adjuster
Indicator Mark
Calibration
Plate
Dial
Stop
SERVICING continued
6. Remove the thermostat dial, making sure not to disturb
the setting.
7. Hold the calibration plate and loosen the two calibration
locking screws.
8. Turn the calibration plate counter – clockwise to increase
the oven temperature or clockwise to decrease it.
NOTE: One division of the calibration plate is equal to 25°F
(14°C).
9. Hold the plate and tighten the screws.
10. Replace the thermostat dial.
11. Recheck the calibration as specified in this procedure to
confirm that the correct adjustment has been made.
Fryer
The same observation made about oven thermostats applies
to fryers. That is, recalibration of the thermostat is seldom
necessary. If experience with the cooking results proves that
the temperature at which the dial is set is incorrect, follow
this procedure to re-calibrate the thermostat. Use a reliable
thermometer only or, preferably, a pyrometer.
1. Suspend the thermometer or thermocouple in the
middle of the fry tank about 2” (76mm) below top level of
oil.
2. Allow the burner to cycle four times.
3. When the burner cycles OFF after the fourth cycle,
compare the reading of the thermometer or
thermocouple with the thermostat setting.
4 If the two readings are not within ±5°F (±3°C) of one
another, loosen the two set screws in the thermostat
knob and set the pointer of the thermostat to agree with
the reading of the test thermometer or thermocouple.
5. Tighten the set screws on the thermostat knob after
resetting the pointer.
Summary of Contents for Master MST42R
Page 32: ......