There are two types of thermostats used on most Whirlpool, Kenmore, GE, and Maytag electric and gas dryers – Fixed and Adjustable. These two types have three basic applications in a dryer – as operating or cycling thermostats, safety thermostats, and cool-down thermostats.
An operating or cycling (bias) thermostat is used to control the air temperature in the dryer. A single fixed thermostat, several switch-selected fixed thermostats, or an adjustable thermostat may be in control. These thermostats are located in the exhaust airstream of the dryer and have normally closed contracts. The contacts open with temperature rise and control the electrical current to the gas burner or electric-heat-element circuitry. In some applications a second, normally open, contact is used to control timer operation lg dryer repair pasadena.
Safety thermostats are employed to prevent excessive temperatures within the dryer. Dryer safety thermostats, or thermal fuses, are always fixed, or the non-adjustable type. They are located at strategic locations in the burner area, heater element housing, or fan-scroll housing, depending on the design of the dryer model. In most, if not all dryer applications, thermal fuses and safety thermostats have normally closed contacts that open the circuit and prevent electrical current to the heat source in the event that some failure or an abnormal rise in temperature. Some of the earlier dryer safety thermostats used with some manual ignition burners had normally-open contacts that close and energize an unlatching solenoid.
Cool-down thermostats are used to provide motor operation during the cool-down on many Whirlpool and Maytag Dryer designs. These thermostats have normally-open contacts that close during the heat phase of the cycle. At the end of that phase, the timer or relay contacts are opened and the dryer continues to run without heat. When exhaust temperatures drop to approximately 120F, the contacts open to end the cycle.