Dryer Running, Not Heating
The list below are the most common failures when you have a dryer
that runs but does not heat. There are a number of parts that
can cause this dryer issue.
Power Problem
With most dryer repairs, the first thing you always want to do is
make sure your dryer is getting the proper voltage to run correctly.
It is possible for half a double pole breaker to be kicked.
This means the motor is getting power to run, but the heating
element is not able to run. Check your power cords for any
signs of damage or burn marks. Check for blown circuit
breakers in your house electrical panel.
Heating Element
This is the component that creates the heat in your electric
dryer. It requires 220 Volts AC to heat properly.
Heating elements come in all shapes and sizes. Basically they
all work the same though, a coil of wire that glows red hot.
Igniter
The igniter is what lights the gas that has entered the dryer
throught the gas valve. It will glow red hot, then when it
reaches a certain temperature, it will trigger a thermostat that
allows the gas to flow through the valve and into the burner.
That's when your dryer should start to heat up and everybody is
happy. If the igniter fails, then the motor will still run,
but the dryer will not heat and your clothes will not dry.
Flame Sensor
This is the sensor that detects that the igniter is working
correctly. An easy way to tell if the flame sensor is the
problem is simple. If the igniter comes on then cycles off
after about 15 seconds or so, the flame sensor is fine. This
would idicate an issue with the coils on the gas valve. If the
ignitor comes on and does not cycle off, then the flame sensor would
need replaced.
Gas Coils
These are the little round coils that sit on top of the gas valve
that have the wire connections on them. These are the most
common problem for gas dryers that are not heating. If the
igniter is glowing red hot and cycling on and off like it's supposed
to, then you would need to replace the coils. To test the
coils is pretty simple, first you would remove the wires going to
them, then check resistance across the two terminals on them.
You should get in the neighborhood of 1300 ohms give or take.
Motor Switch
The motor switch is on the dryer's motor. It is activated
when the motor starts to spin when you press the start button.
This is the click you heat when it first starts up. It is
possible for the contacts inside the switch to go bad. The
heater circuit passes through this switch. A malfunction of
this switch will cause the dryer to run, but not heat. The
whole motor would have to be replaced to fix this issue.
Limit Thermostat
These are the thermostat that allow the dryer to maintain a
certain temperature. They cycle the heater on and off to
provide the proper temperature for your clothes to dry. If one
of these thermostats fails, the heater will not be able to come on
and your clothes will not dry. The same thing will happen with
both gas and electric dryers.
Safety Thermostat
The safety thermostat is a non-resettable thermostat that sits on
top of the heater assembly. When this thermostat trips, it's
usually do to a poor airflow issue. This is telling you that
you have a problem and need to fix it. If the temperature of
the heater rises above a certain temperature this will trip.
During normal operation the thermostat does not reach this
temperature. I've just learned a little trick for these
thermostats. They are in fact resettable. You just need
to know how to do it. Watch the video to the right here and
learn how to repair this at no cost.