Snap-disc bimetal thermostats with spade terminals, similar to the cycling and high-limit thermostats in dryers and ovens

Generic photo: Retired electrician · CC0

How to test a dryer cycling (operating) thermostat

The cycling thermostat switches the heat on and off to hold the exhaust temperature. It should be closed when cold and open when hot. A stuck-closed unit overheats the dryer; a stuck-open unit gives no heat.

Cross-checked ~20 min easyBrands: All

Before you start

Unplug the appliance or turn off the breaker before opening panels or disconnecting parts
Take a photo of the wiring before removing any wire
Resistance and continuity tests are done with power OFF and the part isolated
Live-voltage checks are a caution step: insulated probes, one hand, clips attached before power is restored, stay clear of terminals

Diagnostic steps

Unlock all 6 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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