How To Repair A Dryer That Won't Stop Running

The door switch only allows the dryer to run when the door is fully latched. So it’s possible that your dryer won’t stop tumbling because the signal that the door’s really open isn’t being sent. Depending on your model, you’ll usually find the switch poking through the front panel into the dryer door frame. Unplug the dryer, and use your multi-meter to check for continuity. Test between the C terminal and the NO terminal: you ought to get infinite ohms if the door switch button is up or the door itself is open.

If your dryer doesn’t have an electronic main control board, it probably uses a mechanical timer instead. This can be found in the control console, and uses a small motor to operate cams and switches to control the dryer functions. A shorted contact in the timer could cause the dryer to stay running.

If your gas or electric dryer isn’t ending the Auto Dry cycle when the clothes are dry, it may be the fault of a defective cycling thermostat. This part governs the temperature of the dryer as well as the timer motor on Auto Dry models. A defective thermostat may not allow the timer to advance to the off position and continue to run. You’ll find the cycling thermostat in the internal airflow ducting, generally on the housing of the blower. Since the correct way to test whether the cycling thermostat is advancing the timer is with the dryer actually running, a test on whether the thermostat’s playing its part in this sequence should only be done by a service technician. If you truly do not want to pay for repair work, you can eliminate all the other potential sources of trouble in your timer, door switch, and cool down thermostat, and then just replace the cycling thermostat if all else is fine. A new thermostat might cost less than a technician’s visit.

If your dryer tumbles the clothes even once they are dry, to fluff them or to reduce wrinkling, it may have a cool down thermostat governing this function. This thermostat regulates the power coming into the drive motor, keeping the drum turning until the temperature inside the drum hits a certain point. So a failure in the cool down thermostat would keep the drum turning too long, or even until you interrupt it manually by opening the door. You can unplug the dryer and use your multi-meter to check for continuity in the cool down thermostat, usually located near the blower wheel housing.