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 high-limit thermostat (dryer and similar heaters)

A high-limit is a normally-closed bimetal switch that opens if the heater area overheats and closes again when it cools. A room-temperature continuity test catches the common "stuck open" failure, but it cannot prove the opening temperature is right.

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

Diagnostic steps

Unlock all 5 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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