Whirlpool 4322452 Service Manual page 51

The Thermostat contains a set of contacts that open and close, (see Figure 4-11A), depending
on the temperature selected by the customer, and the temperature monitored in the oven cavity.
When the thermostat is turned to the "ON" position, contacts within the thermostat close to
complete an electrical circuit (see Figure 4-11B). As the oven heats up to a selected temperature,
the internal pressure within the sensing bulb increases until the thermostat contacts are forced
open (see Figure 4-11C).
1. Oven Off
Switch Open
Shaft
Sensor
Actuator
Sensing Bulb
L1
Switch Contacts
As the oven cools, the pressure from the sensor actuator decreases, and the thermostat contacts
close. This cycling of the contacts opening & closing continues until the cooking function is
complete. The electrical contacts of the thermostat complete an electrical circuit through the ignitor
and safety valve to the neutral side of the 120-volt circuit (see Figure 4-12).
Oven
Thermostat
Switch
Contacts
A
Thermostat
2. Oven On
Shaft Rotates Against
Actuator - Switch Closes
B
Figure 4-11
Oven Ignitor
Figure 4-12
Page 4-7
3. Oven Temp Reached
Pressure Expands Sensor Actuator
& Pushes Against Switch Actuator
- Switch Opens - Oven Turns Off
C
200˚ Heat From Oven
Safety Valve
N