Well, this is awkward. You expect that someday your dryer may manifest a problem that will prevent it from functioning at all, but what you didn’t expect was the dryer to just keep running. It keeps rotating, making heat, or just never stops until you physically cut the electricity to it or open the door and trigger the safety mechanism. Because it is something that you don’t really expect, you really probably don’t know how to handle it or even where a troubleshooting investigation should start. We can help with that so you at least know if it is a repair you can handle or not.
The Dryer Setting is Wrong
As this is the easiest cause of the problem to fix, it is the one you want to check first. Is your dryer on an appropriate cycle? One of the issues that you see most these days is that the dryer is accidentally set to low or no heat. As the dryer isn’t on a timer, it measures the moisture of the laundry. A load of jeans you are drying on an air dry cycle will feel like the appliance is going to run forever.
Check the cycle first and try running the dryer on with a different cycle after. This can save you so much time troubleshooting and you don’t feel like a fool for accidentally calling an appliance repair technician to fix what turns out wasn’t actually a problem.
Vent or Filter Clog
Many modern dryers don’t use a timed dry cycle by default anymore. Instead, they use a sensor to determine if the laundry is dry, and it will continue to run until that happens. As you would expect, this will be a popular cause for this issue throughout the list. However, in this case, what is fooling the sensor is a lint clog somewhere in the system.
This issue can cause a lot of different problems. If you haven’t checked your lint filter lately, it becomes even more likely. You will want to check your lint filter, exhaust hose, and vent in your home to make sure no lint is built up and causing a clog. Any lint clogs are not only a serious fire hazard, but they will slow down your laundry. The clog prevents the hot moist air from being vented. As such, it lingers and keeps your laundry damp longer.
If you have a ventless dryer, you have to worry about a similar, yet different issue. Ventless dryer models use a condenser to essentially just collect the moisture rather than venting it away. If the condenser is full or it is all blocked up by dirt or fibers, it will cause the very same problem as a lint clog. The moist air lingers inside the dryer and prevents fast drying.
Faulty Lambda Sensor
The lambda sensor is used in almost all modern dryers now as a measure in energy efficiency. This small metal stripe located at the front, inner edge of your dryer measures the moisture of your tumbling laundry. If the wiring for the sensor gets damaged or, more likely, when the sensor makes contact with the casing, it could cause the dryer to run indefinitely even if your clothing is dry. In some cases, all you may need to do is clean the sensor with white vinegar as fabric softener build up can cause it to malfunction.
Faulty Main Circuit Board
The circuit board is the brain of your appliance. As such, when it malfunctions, it can be to blame for an endless list of different problems including not allowing the dryer to shut off. As the circuit board is malfunctioning, it is likely not sending the correct signals to shut off the appliance. Interestingly enough, replacing the circuit board is more simple than you would expect. The hardest part is actually just the disassembly to reach it.
Faulty Temperature Sensor
Similar to the lambda sensor that detects moisture, if a temperature sensor is faulty, it can result in longer run times. When a temperature sensor is working, but isn’t working correctly, it may not allow the heating element to heat up to the right temperature. If it is below temperature, then it will take much longer for your laundry to dry. Essentially, your dryer won’t run indefinitely, but finishing a load will take a very long time.
This issue isn’t incredibly common, but it can happen. What is more likely to happen is that the temperature sensor will fail the other way. Instead, everything gets too hot and your high limit thermostat will most likely trip to prevent any fires.
Faulty Heating Element
While a faulty heating element is a dryer problem all its own, it can be a contributing factor here if it malfunctions just right. What happens is that the heating element goes faulty and perhaps the temperature sensor as well. The dryer still rotates and runs, but no heat is actually drying the clothing. This creates the perfect storm of the dryer running indefinitely and your clothing never getting dry.
This issue can also happen if your dryer overheated recently. What can happen is that the dryer got too hot and triggered the high limit thermostat. In some models, once the high limit thermostat is tripped, it will cut power to the entire appliance. In other models, it will cut power to only the heating element. The dryer will turn as normal, but your laundry will be ice cold because no heat is being produced. Thus, it will take forever to dry.
Home Electrical Issues
Electrical issues can cause finicky problems. In most cases, if you have electrical issues, it will stop the dryer from functioning. However, if there is not enough current getting to your dryer, if can cause the dryer to still run, but not really dry anything. This can be a common issue if your dryer is plugged into the same outlet as another appliance. You can see this issue when the dryer and washer share an outlet that isn’t getting enough power to run them both at the same time.