Axial thermal fuse, a one-time cutoff that opens when it overheats

How to test a dryer thermal fuse

A thermal fuse is a one-time safety link that opens permanently when the exhaust gets too hot. It is a simple continuity test, but a blown fuse is a symptom: the real cause is almost always a restricted vent or a failed cycling thermostat.

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

Full library + AI assistant for $34.90, one time.

Get lifetime access

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.

More dryers guides

Component test · Dryer

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.

5 steps ~20 mineasy

Component test · Dryer

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.

6 steps ~20 mineasy

Component test · Dryer

How to test a dryer heating element

An electric dryer element is a resistance coil on 240 V. Test it across the terminals and to ground. Most read in the low teens of ohms; use R = V²/W from the element rating to check yours.

6 steps ~40 minmoderate