A dryer fuse is an inch or two long device that plays an important role in preventing fires. Federal law requires to include a thermal fuse on dryers built since the 1980s. The thermal fuse triggers if the exhaust gas temperature of the dryer rises too high. It shuts off all the dryer’s components if this happens. A thermal fuse triggers only once, after that it needs to be replaced.
Symptoms Of The Blown Thermal Fuse on Dryer
Most dryer models will not work once the thermal fuse is triggered. But on some other models, the drum continues to turn on, and the dryer functions, but the heating element does not turn on. Clothes stay wet once the dryer completes its cycle.
Locate the Fuse
Thermal fuses are located on the exhaust duct of the dryers. You need to take off the dryer’s back panel to access the fuse. When you start looking for it, first turn off the dryer, or better, disconnect it completely from the mains. The shapes and sizes of thermal fuses vary. Some are made from metal; others are plastic. Look for a small device about 2 inches long; it is usually positioned right on the top of the exhaust duct. The thermal fuse on dryer has two wires connected to it. For better understanding how thermal fuse looks like, please check this link.
Bypass Method
A decent way to test whether a thermal fuse has burned out is to disconnect and run the dryer without the fuse temporarily. However, it is tempting to use your dryer without it, but it’s highly not recommended. Bypassing the thermal fuse is only to detect whether the fuse is blown. It is not a permanent solution. Disconnect two wires from the fuse and connect them with a jumper wire, then run the dryer. If it goes on and heats, the thermal fuse is blown and needs to be changed.
Use An Electrical Tester
Use an electrical tester for a better and faster way. Remove wire leads from the thermal fuse and touch a tester probe to wire terminals on the fuse. If you get an infinity reading, the fuse is OK.
If you get an infinity sign, the fuse is OK. If you get other signs less than infinity, it means the thermal fuse is triggered and needs to be replaced.
Troubleshooting
Change the thermal fuse with an exact match for your dryer model. Then check the dryer for the reason why the fuse is blown. Sometimes, because of the age, the thermal fuse burns out; other times, something else fails and causes exhaust temperature to rise. Make sure the power is still disconnected, and start for troubleshooting and examine the exhaust duct for obstacles that restricted airflow. Check the fan blades of the blower motor for damage and make sure that the motor is not connected. Along with the thermal fuse, you may also want to replace the dryer cycling thermostat. If this thermostat fails, it will probably trigger the thermal fuse.
If you still not sure you can handle that, better call professionals, to avoid further damages to your appliance.