Pilot failures fall into one of two categories – failure to light or failure to remain lit.

Pilot Fails to Light

1.Gas is not being supplied to the valve: Check for a closed gas cutoff valve upstream of the gas valve. Also verify that the gas line quick disconnect fitting at the rear of the fryer (if so equipped) is properly connected.

2.Blocked pilot orifice: If gas is reaching the valve but the pilot will not light, check for an obstruction in the pilot orifice, especially in new installations. If the orifice is clear, check to be sure that the pilot adjustment screw is not completely closed.

Pilot Does Not Remain Lit When Gas Valve Knob is Released

The gas valve used on Dean millivolt fryers has a pair of normally open coils (electromagnetic switches) that close when low voltage is applied to them. If the coils do not close, the valve will not open to supply gas to the pilot or to the burner manifold. Turning the gas valve knob to the pilot position and pressing it in bypasses the pilot coil, allowing the pilot to be lit. The pilot flame heats the thermopile, which generates the voltage required to close the coils. If the pilot flame goes out when the knob is released, there are four probable causes:

1.Open or grounded high-limit:The high-limit thermostat functions as a normally closed switch. If the high-limit is open or grounded, the gas valve coil will not pull in and no gas will be supplied to the pilot or to the burner manifold.

Check and Corrective Action: Detach the high-limit leads from the gas valve and check for continuity. See page 1-10. If the high-limit fails the continuity check, it must be replaced.

2.Loose/corroded wiring connections on high-limit or thermopile: This has the same effect as a grounded or open high-limit. If the gas valve coils do not receive the appropriate voltage from the thermopile, they will not close and no gas will be supplied to the pilot or to the burner manifold.

Check and Corrective Action: Check wiring connections for corrosion and tightness. Check terminals to verify that they are securely attached to their leads.

3.Low or no voltage out of thermopile: If the pilot flame does not surround the tip of the thermopile, it will not generate sufficient voltage to the gas valve coils for them to close. No gas will be supplied to the pilot or to the burner manifold.

Checks and Corrective Actions: Observe pilot flame located between the middle burners on the frypot. If the pilot flame is less than 1-½ inches (38 mm) adjust the pilot flame in accordance with Section 1.6. If the flame is being blown away from the thermopile, eliminate the draft that is causing the problem.

If the pilot flame correctly surrounds the tip of the thermopile, see D on Page 1-9.

4.Malfunctioning gas valve: If either of the coils in the gas valve fails, no gas will be supplied to the pilot or to the burner manifold.

Check and Corrective Action: See page 1-10 for check procedures to see if the gas valve has failed. Instructions to replace the gas valve are found in section 1.7.3.

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Frymaster Super Runner Series, Super Marathon Series manual Pilot Fails to Light