Frymaster Dean FPHD - Manual (Page 7)

HIGH EFFICIENCY DECATHLON SERIES GAS FRYERS
CHAPTER 1: SERVICE PROCEDURES
1-2
1.1 Functional Description
(cont.)
Pilot System Configuration
The pilot system is comprised of the pilot orifice, pilot hood, and a thermopile (some systems
incorporate a thermocouple). The pilot serves two purposes: light the burner and heat the
thermopile. In operation, the thermopile is in contact with the pilot flame and generates millivolts.
The millivolt output energizes the gas valve pilot coil, which in turn opens the pilot valve. If the
pilot flame is extinguished, the gas valve pilot coil loses voltage and the pilot valve closes. The
main valve of the gas valve will not open if the pilot valve is not open. The pilot flame must be
manually lit when the fryer is first placed into operation. A separate 24V circuit, activated by the
fryer ON/OFF switch, provides voltage through the Thermatron to the gas valve main coil, which
opens the main valve.
Electronic Ignition Configuration
In units configured for electronic ignition, an ignition module connected to an ignitor assembly
replaces the pilot system. The ignition module performs three important functions: It provides an
ignition spark, supplies voltage to the gas valve, and proofs the pilot flame.
The module contains a 90-second time delay circuit and a coil that activates the gas valve. The
ignitor assembly consists of a spark plug, a pilot, and a flame sensor element.