What Is a Thermocouple in a Clothes Dryer?
A thermocouple, or thermal fuse, is a safety mechanism found in most clothes dryers. It's essentially a fuse that immediately turns off power to the heater, and sometimes the dryer, when the dryer overheats. The thermocouple only activates when the drum's air temperature gets hot enough to reach the fuse's preset trip temperature.
Most people probably don't realize that their clothes dryer even has a thermocouple, especially if their dryer never overheats. It's usually nothing more than a small, flat piece of plastic with two wires coming out its side. The plastic covering holds a fuse that's safely housed inside.
After a thermocouple blows, you often have to reset the dryer's circuit breakers to restore some of the dryer's function. Unfortunately, your dryer likely won't operate fully until you replace the thermocouple. If it works at all when the fuse is blown, its operation will be irregular at best. For example, it might be slow to heat or not heat at all, and the drum might tumble weakly or stop completely. The only way to fix this is to replace the thermocouple.
Where It Is
Before you attempt to locate the thermocouple, disconnect power to your clothes dryer to prevent electrical shock. You can usually find the thermocouple near the vent collar or behind the back panel cover on most dryers. However, it's best to review your dryer manual to confirm its location before attempting to find it to save yourself time and aggravation. Once you either remove the collar or panel, you'll probably see a cluster of wires bundled together. The thermocouple is often found close to the wire cluster.
It's relatively easy to replace a bad thermocouple. In fact, once you've identified the bad thermocouple, you're nearly halfway complete with the repair. From here, all that you need to do is to label each of the bad thermocouple's wires before you carefully remove them. Reconnect the wires to the proper connection points on the new switch and replace the collar or panel. However, if you don't feel comfortable making the repair on your own, contact a dryer-repair technician to handle it.