Appliance tip of the week...

Model Number: 110.78942890

Brand: Sears Kenmore

Age: More than 10 years

My gas dryer only has high heat. A month ago it had no heat and I had it repaired, replaced the coils. It worked for about 4 weeks, now low/medium won't work.

Any suggestions on what could be wrong?

Does this happen on auto dry or timed dry? or both?

As a test, pull your dryer out from the wall, then take the exhaust hose off the dryer completely, then run a test load and see if you get the same results or not.

If its still doing it, then its possibly your thermistor or control board.

First you'll need a multimeter to ohm test the thermistor, unplug the dryer first and remove the 2 wires from it, then it should read 10K ohms (10,000) ohms at room temperature.

The thermistor, Its #42 here.

It mounts on the blower wheel housing, and sits next to the white thermal fuse.

Remove the two #3 screws to take off the #45 lint duct assembly to get good access to it.

Here's the thermistor for your model you can order here if needed: Manufacturer part# 8577274.

The lower access panel unclips as you can see here, two clips on each side, I use a putty knife and push-in on the two clips here.

Let us know how the repair goes.

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