SERVICE PROCEDURES AND ADJUSTMENTS
MILLIVOLT CONTROLS TEST
1.Verify proper gas (natural or propane) is present.
2.Check for correct wiring and secure connections.
3.Verify the pilot flame is adjusted properly as outlined in Pilot Adjustment.
4.If the pilot is not lit, light pilot as outlined under Lighting Pilot. Allow the pilot to burn for 3 to 4 minutes to stabilize.
A.If the pilot remains lit, proceed to step 6.
B.If the pilot will not remain lit, proceed to step 5.
5.Connect DC voltmeter to terminals TH TP and TP of combination valve. Relight the pilot, hold the combination valve knob in and allow the pilot to burn for 3 to 4 minutes to stabilize.
A.If the voltage measures 450 millivolts or greater and the pilot will not stay lit, replace the combination valve.
B.If the voltage is less than 450 millivolts, measure the voltage at terminals NO and C of high limit.
1)If the voltage is 500 millivolts or more, replace the high limit.
2)If the voltage is less than 500 millivolts, disconnect the lead wire from terminal TH TP of the combination valve and remeasure voltage at the high limit.
a.If the voltage is less than 500 millivolts, replace the thermopile.
b.If the voltage is 500 millivolts or more, replace the combination valve.
6.Connect DC voltmeter to terminals TP and TH of combination valve.
7.Turn combination valve to ON. Turn thermostat to a setting higher than the shortening temperature.
A.If the voltage measures 150 millivolts or more but the burners do not ignite, replace the combination valve.
B.If the voltage is less than 150 millivolts, measure the voltage between terminals NO of the high limit and TP of the combination valve.
1)If the voltage is 200 millivolts or greater, replace the thermostat.
2)If the voltage is less than 200 millivolts, replace the combination valve.
THERMOSTAT CALIBRATION
1.Place temperature tester in the fry tank near the thermostat bulb.
2.Set the thermostat to 300°F and allow the temperature to stabilize.
3.Check the temperature tester reading against the thermostat dial reading. If there is a variance of more than ±20°F (280°F to 320°F), calibration is required.
Calibration Steps
1.Remove thermostat knob from shaft.
2.Using a small screwdriver, rotate the setscrew inside the hollow shaft counterclockwise to increase the temperature or clockwise to decrease the temperature (1/4 turn equals approximately 18°F).
3.Allow temperature to stabilize and recheck temperature. Repeat until the temperature falls within the limits as stated in step 3 under Thermostat Calibration.
4.Install thermostat knob and set dial to 350°F.
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