Start with the easy checks
- The breaker (electric dryers). Electric dryers run on a 240-volt double breaker. One half can trip while the other stays on, which leaves the drum turning with no heat. Switch the dryer’s breaker fully off, then back on.
- The gas supply (gas dryers). Make sure the gas valve behind the dryer is open and that other gas appliances in the house are working.
- The settings. Air Fluff and Wrinkle Release settings don’t use heat. Try a regular timed dry.
- The lint screen and the vent. Clean the lint screen, then go outside while the dryer runs and check that air is coming out of the vent hood with some force.
Why the vent matters so much
A dryer needs to move hot, damp air out of the house. When the vent is clogged with lint, crushed behind the dryer or simply too long, heat builds up inside the dryer. Safety devices then cut the heat, and some of them, like the thermal fuse, are one-time parts that have to be replaced. That’s why a dryer that stops heating so often has a vent problem behind it.
It’s also a fire risk. According to the U.S. Fire Administration, failure to clean is the leading cause of home dryer fires. If your drying times have been creeping up, have the vent checked even after the heat is fixed.
Common causes in electric dryers
Thermal fuse
A small safety fuse on the exhaust duct that blows when the dryer overheats. On many models a blown thermal fuse stops the heat only. On others it stops the whole dryer. Replacing the fuse without fixing the airflow means it will blow again.
Heating element
The coil of wire that makes the heat. Elements can break, especially on older dryers or ones that have been running hot. A technician confirms it with a continuity test.
High-limit and cycling thermostats
These switch the element on and off to hold temperature. A failed thermostat can leave the element off even though it’s fine.
Common causes in gas dryers
Igniter
The glowing part that lights the gas. If it doesn’t glow, or glows but the gas never lights, the igniter or the parts around it may have failed.
Flame sensor
Tells the dryer the flame is lit. A failed sensor can shut the gas off early or keep it from opening.
Gas valve coils
Small electrical coils that open the gas valve. A common sign of failed coils is an igniter that glows, goes out, and the dryer never lights, or lights once and then won’t relight.
If you smell gas near your dryer, don’t run it or switch anything on or off. Leave the house and call SDG&E or 911 from outside.
What to tell your technician
- Electric or gas, plus the model number from the label inside the door or on the back panel.
- Whether there’s no heat at all, or some heat that isn’t enough.
- How long drying took before the problem started, and whether it had been getting slower.
Is it worth repairing?
Almost always. Dryers are simple, durable machines, and fuses, thermostats, elements and igniters are all straightforward repairs.
If you’re in North County San Diego, you can book a dryer repair with “Not heating” already filled in. The diagnostic visit is $89 for homes and $129 for commercial properties.
