Dryer Thermostat Not Working

A dryer thermostat that is failing does not always mean no heat at all -- it more often shows up as clothes coming out too hot, still damp after a full cycle, or a dryer that runs noticeably longer than it used to before the auto-dry sensor decides the load is finished.

Modern dryers actually use two different kinds of temperature sensing: a cycling thermostat (or high-limit thermostat) that physically opens and closes to regulate heat and cut power if the unit overheats, and, on many newer models, an electronic thermistor or moisture/radiant sensor that reports drum temperature and dryness to the control board so it knows when to end the cycle. A failure in either one produces a similar complaint -- "the dryer runs hot" or "clothes are still damp when the buzzer goes off" -- but they are different parts.

If your dryer produces zero heat at all rather than inconsistent heat, start with Dryer Not Heating instead, which covers the thermal fuse and heating element in depth.

Safety first. Dryers combine household electricity, a spinning drum and motor, and -- on gas models -- a live fuel line.

  • Unplug the dryer, or shut off the breaker for a hardwired unit, before removing any panel or touching internal components.
  • Gas dryers: shut off the gas supply valve behind the unit before working on it. If you smell gas at any point, leave the area immediately and call your gas utility from outside -- do not flip switches or search for the leak yourself.
  • Lint is flammable. A clogged lint trap or exhaust vent is a fire hazard, not just a performance problem -- treat a dryer that runs hot, or a thermal fuse that keeps blowing, as a reason to check the vent, not just replace the part.
  • Call a licensed technician if you are not confident identifying or safely accessing a part.

Most Likely Causes

  1. Cycling thermostat / high-limit thermostat — The most common cause of erratic heat. This thermostat opens and closes to keep drum temperature in range and can fail stuck open (dryer runs too hot or shuts off on the safety circuit) or stuck closed (dryer never reaches temperature and clothes stay damp). Parts sold as Dryer High-Limit Thermostat (3977767) or Kelvinator Dryer High-Limit Thermostat (3204267) cover this component.
  2. Radiant sensor / moisture sensor — On dryers with an automatic dry cycle, this sensor tells the control board how damp the load still is. A failed or coated sensor (fabric softener residue is a common culprit) reports false readings, so the cycle ends too early or runs far longer than needed. Sold as Dryer Radiant Sensor (338906 or 5303281135).
  3. Electronic thermistor — On electronically controlled dryers, a thermistor reports drum temperature to the control board the way the older mechanical thermostat does mechanically. A drifting or failed thermistor causes the same over-hot or under-dry symptoms. Sold as Dryer Thermistor (8577274).
  4. Control board — Less common. If every thermostat and sensor tests normal but the temperature behavior is still wrong, the board itself may be misreading or misresponding to sensor input.

Both electric and gas dryers use the same cycling and high-limit thermostats to regulate drum temperature -- the thermostat itself does not differ by fuel type, only the heat source it is regulating does (a heating element on electric models, a gas burner and igniter on gas models).

How to Check Each Part

Check Your Exact Model

Once you have narrowed the cause down to a part type, confirm it against your exact dryer rather than guessing from the brand alone. Use the model and part lookup tool to search by your dryer's full model number, or start from one of these confirmed model pages to see the exact parts list for that unit:

Related Symptoms

If this is not quite the problem you are seeing, browse the full list of repair symptoms.

SymptomWhat it looks like
Dryer Not HeatingDryer runs but produces no heat at all
Dryer Thermal Fuse BlownDryer has no power to the drum or heater at all
Dryer Taking Too LongCycle runs far longer than it used to
Dryer Stops Mid-CycleDryer shuts off before the cycle finishes

Still not sure? Use the model and part lookup tool to search by your appliance model number directly.

How to Confirm Before You Buy a Part

Before ordering any replacement part, take a minute to confirm fitment -- it is the difference between a repair that works the first time and a part that has to be sent back.

  1. Find the model/serial plate. On most dryers it is inside the door opening (printed on the frame you see when the door is open), behind the lint trap housing, or on the back panel near the power cord. See how to find your model number if you cannot locate it.
  2. Read the full model number exactly as printed, including every letter and dash -- manufacturers reuse near-identical model numbers across different production runs that take different parts.
  3. Verify the part fits that exact model using the model and part lookup tool before you buy, rather than assuming a part that looks the same will fit.

The full model number matters more than the brand and appliance type alone. Manufacturers commonly reuse one body design across many model numbers over several years, changing the exact door switch, control board, or heating circuit partway through the run -- so two dryers that look identical side by side can still take different parts.