Whirlpool 4322452 Service Manual page 54

When current flows through the ignitor, heat is applied to the bimetal strip. The amount of heat
necessary to warp the bimetal enough to open the valve requires 3.0 amps of current flow in the
circuit (see Figure 4-18). The reason the valve is designed not to open below 3.0 amps, is to insure
that the temperature of the oven ignitor is above 1800˚F before the valve opens. The operation of
the system is complete when gas is flowing from the safety valve to the oven burner, and is ignited
with the hot glo-bar ignitor. The entire process may take between 40 to 60 seconds to start.
Gas Outlet
(To Oven Burner)
120 Volt
Supply Terminal
Safety Valve
Gas Inlet
(From Regulator)
Current Warps Bimetal
Figure 4-18
& Valve Opens
Throughout the cooking cycle, the oven will continue to "heat up" and "cool down" to maintain the
selected temperature (see Figure 4-19). This operation is controlled by the thermostat's sensing
bulb.
L1
N
Thermostat Switch
Contacts Closed
Oven Is Heating
To Oven Burner
Oven Glo-Bar
Ignitor
3.0 Amps
Safety Valve
Safety Valve Opens
& Gas Flows
To Oven Burner
L1 N
Thermostat
Switch Contacts Oven Ignitor
Safety Valve
Figure 4-19
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