Frymaster PERFORMANCE PRO SERIES 45 Service And Parts Manual page 21

The Electronic Circuits
If the fryer is receiving gas and electrical power, the next most likely cause of ignition failure is a problem
in the 24 VAC circuit of the pilot system. If the fryer is equipped with a drain valve for fi ltration purposes,
check the drain valve to verify that it is fully closed. A microswitch attached to the valve must be closed
for power to reach the gas valve. Often, although the valve handle appears to be in the closed position, the
microswitch is still open. If the valve is fully closed, or the fryer is not equipped with a fi ltration system,
refer to Troubleshooting the 24 VAC Circuit in Section 1.7.1 of this manual.
The Gas Valve
If the problem is not in the 24 VAC circuit of the pilot system, it is most likely in the gas valve. However,
before replacing the gas valve, refer to Troubleshooting the Gas Valve in Section 1.7.2 of this manual.
Improper Burner Function
In these types of instances, the burner ignites but exhibits abnormal characteristics, such as popping,
incomplete lighting of the burner, fl uctuating fl ame intensity, and fl ames "rolling" out of the fryer.
Popping indicates delayed ignition. In most cases, the main gas valve is opening, but the burner is not
immediately lighting. When ignition does take place, excess gas bursts into fl ame suddenly, rather than
smoothly igniting.
The primary causes of popping are:
1. Incorrect or fl uctuating gas pressure
2. Misdirected or weak pilot fl ame
3. Clogged burner orifi ces
4. Inadequate make-up air
5. Missing or misaligned burner defl ector targets
6. Clogged vent tube (causing incorrect gas pressure).
Incorrect or Fluctuating Gas Pressure
If popping occurs only during peak hours, the problem may be incorrect or fl uctuating gas pressure.
Verify that the incoming gas pressure (to the gas valve) is in accordance with the appropriate CE or non-
CE standard found in the table on Page 1-4 and the pressure remains constant throughout all hours of
usage. Refer to Checking the Burner Manifold Pressure in Section 1.3.2 for instructions on checking the
pressure of gas supplied to the burner.
Misdirected or Weak Pilot Flame
If popping is consistent during all hours of operation, check position of the pilot above the burner orifi ce
and verify that the pilot pressure is correct. A 1- to 1 ½-inch (25 to 38 mm) fl ame indicates correct pilot
pressure. Refer to Section 1.3.3 for information on pilot fl ame adjustment.
Clogged Burner Orifi ces
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