Unless your closet is filled with strictly drip-dry clothing, you expect your gas or electric dryer to earn its keep and efficiently dry your clothes after washing. But if you discover your shirts, blouses, pants, or underwear are still moist after running a full drying cycle, there should be little doubt that the appliance has failed to live up to its side of the bargain.
What happens when the dryer stops heating?
An average load of clothing will take about 60 minutes to thoroughly dry in both gas and electric dryers. But to do this, the air that is drawn in through the front or rear of the appliance by the blower wheel needs to be heated properly. The hotter the air, the more effective it will be at removing moisture from the clothing as the items are tumbled by the rotating drum. If the dryer begins running after the start button is pressed, and the drum is turning as expected, but the clothing remains damp after the drying cycle ends, it’s most likely due to the air not being heated as it should before being drawn through the rotating drum.
Both gas and electric dryers require adequate air flow to get the job done. This is why the dryer should always be located in an open, well-ventilated area with the rear of the appliance kept several inches from the wall. But the location of the dryer is not the only thing that can impede air flow; an obstruction in the venting can do this as well.
Cleaning the venting is crucial to good dryer maintenance
Small particles of loose fabric from clothing and linens will form lint which collects in the dryer’s lint filter after each drying cycle. Over time, the lint can build up in the dryer’s venting and create an obstruction. This reduces air flow, making the drying process less efficient, and can also cause the dryer’s thermal fuse to “blow” due to overheating. If the thermal fuse blows, the dryer won’t heat up at all until the fuse is replaced. To ensure good air flow, you should detach the venting from the rear of the appliance and use a vent brush to clean out the lint and any other debris at least once a year. You can also use a vacuum cleaner to periodically clean out the filter housing, and, of course, you should always clean out the dryer’s lint filter every time you use the appliance.
Top 5 reasons gas dryer won’t heat
So, your dryer is in a well-ventilated area and you’ve cleaned out the venting, but the appliance still won’t dry your clothes? Now we’re talking about a component failure. Here are the top five parts that are most likely to fail on a gas dryer:
- Blown thermal fuse – As we mentioned earlier, the thermal fuse, usually located on the blower housing and/or near the burner assembly, will blow and cut off power to the burner if the dryer overheats. You can use a multimeter to test the fuse for continuity – a continuous electrical path present in the part. If the fuse tests negative for continuity, it has blown and will need to be replaced.
- Defective gas valve solenoid coils – The solenoid coils open the gas valve, allowing gas to flow into the burner tube where it can be ignited by the igniter. A solenoid can fail several minutes into the drying process which will prevent the dryer from heating the air properly. If you observe the igniter glowing and then shutting off without a flame appearing, then one or more of the solenoid coils is probably defective.
- Faulty igniter – Located right next to the burner tube, the igniter element should get hot enough to ignite the incoming gas. A faulty or weakened igniter will be unable to ignite the gas to heat the air. As with the thermal fuse, you can use a multimeter to test the igniter for continuity. If the igniter tests negative for continuity, it will need to be replaced.
- Malfunctioning flame sensor – The flame sensor, located next to the igniter, is a bimetal component. The heat from the igniter will open the bimetal which increases the voltage to the solenoid coils allowing them to open the gas valve. The heat from the resulting flame will then keep the flame sensor circuit open. If the sensor malfunctions, the gas valve may not open. The bimetal should be closed, allowing for electrical continuity, when the dryer is not in use, so if the component tests negative for continuity at room temperature, you know the part is defective.
- Failed thermostat – A high-limit thermostat, located on the burner assembly, monitors the dryer temperature, and will shut off the burner if the dryer overheats. A cycling thermostat, normally located on the blower housing, will cycle the burner on-and-off to regulate the air temperature. If either of the thermostats fail, the dryer may not heat up the air. Again, you can use a multimeter to test both thermostats for continuity.
Top 5 reasons electric dryer won’t heat
An electric dryer uses a different method to heat the air than a gas model does, so it has some unique parts that can fail or reasons why the air isn’t being heated. Here are the top five parts/reasons you should be aware of:
- Blown thermal fuse – This one is always the top reason for why both gas and electric models will fail to heat up. Remember, the thermal fuse will often “blow” if the venting is obstructed, so clean out the venting regularly.
- Burned-out heating element – Unlike the burner assembly on a gas dryer, an electric dryer uses an electric heating element to warm the air before it enters the drum. As with the thermal fuse and thermostats, you can use a multimeter to test the heating element for continuity to help determine if the part has burned out.
- Faulty thermostat – Electric dryers have high-limit thermostats and cycling thermostats just like gas models do and they can fail in the same way. Again, the best way to determine thermostat failure is to test the component for electrical continuity using a multimeter.
- Incoming power problem – While gas dryers only required 120 volts of alternating current to operate, most electric dryers require 240 volts running through two legs, each carrying 120 volts. If one leg of voltage is shut off by a tripped breaker or a blown fuse, the dryer may still be able to run, but it won’t heat the air. You can set the multimeter to “Volts AC” and test the electrical outlet to determine if 240 volts are present (keep in mind that readings can vary between 210 and 240 volts).
- Defective main control board – The dryer’s main control board could be defective as well, although this isn’t a common problem. While the board cannot be easily tested, you can always inspect it for signs of burning or a shorted out component.
Keep your gas or electric dryer heating up with Repair Clinic
Whether you need a new thermal fuse, igniter, heating element, or gas valve solenoid to keep your dryer heating as it should, Repair Clinic makes it easy to find the exact part that fits your dryer model, including those manufactured by Whirlpool, Electrolux, Kenmore, GE, Maytag, LG, and Samsung. To get started, enter the full model number of the dryer in the Repair Clinic website search bar for a complete list of replacement parts compatible with your appliance. You can then use the “Part Category” filter (“Fuse, Thermal Fuse & Breaker”) and the “Part Title” filter (“Thermoprotector”) to identify the specific part you need. In addition to millions of replacement parts, Repair Clinic also has thousands of “how-to” videos, diagrams, and articles to help you do the repair quickly and successfully.