Pull a load out and find it scorching hot, or notice the dryer keeps heating even after the cycle should have cooled down? A dryer that will not stop heating is more than an annoyance. Excess heat can damage clothes and become a safety concern, so it is worth fixing quickly.
Here is why a dryer overheats and how to bring the temperature back under control.
This article will teach you:
- What controls dryer heat
- Why it can get stuck on
- The parts to test
- When to stop and get help
Why the Heat Won’t Shut Off
Your dryer’s heat is switched on and off by thermostats and a relay working together. When heat will not stop, the usual causes are:
- A stuck cycling thermostat that no longer opens to cut power to the heat source.
- A welded heat relay on the control board that stays closed.
- A shorted heating element that keeps drawing power even when it should be off.
- Restricted airflow that traps heat and drives temperatures up.
What You’ll Need
- Your owner’s manual
- A multimeter
- A screwdriver and nut driver
How to Diagnose Constant Heat
Take these steps carefully, with the dryer unplugged when testing.
- Check airflow first. Clean the lint screen and clear the vent so trapped heat is not the real cause.
- Test the cycling thermostat. With power off, check it for continuity; a thermostat stuck closed keeps the heat on.
- Inspect the heating element. A shorted element can heat continuously even when the control tries to shut it off.
- Consider the relay. On electronic models, a welded heat relay on the board keeps power flowing to the element.
Pro Tip: Constant heat with weak airflow can push a dryer into a real hazard. If the cabinet is very hot to the touch, stop using it until you have found and fixed the cause.
When to Look a Little Deeper
Because overheating and heat loss share the same thermostats and element, comparing symptoms helps, and reviewing a Kenmore dryer that is not heating or a GE dryer that is not heating shows how the same parts fail in the opposite direction. Runaway heat can also trip protection and mimic a dryer that shuts off after starting.
When a safety part is at fault, you can replace a high-limit thermostat, or confirm whether a thermal fuse has blown.
When to Call a Pro
If the thermostats test fine and the dryer still overheats, a welded control-board relay is likely. Because overheating is a safety issue, having a technician diagnose the board is the safe move.
Wrapping Up
A dryer that will not stop heating needs prompt attention. Here’s the recap:
- Clear the lint screen and vent first.
- Test the cycling thermostat for a stuck-closed condition.
- Inspect the heating element for a short.
- Suspect a welded relay if parts test good.
Find the stuck part and your dryer will cycle heat safely again. Stay safe and take your time.