A job in a basement in Cleveland made me rethink how I test dryer thermostats

I was replacing a heating element on an old Whirlpool dryer, and the customer said it kept shutting off after 10 minutes. I checked the usual suspects, but everything tested fine with my meter. Out of ideas, I ran it empty and put my hand on the exhaust duct after the drum. It was cool, which meant the thermostat on the blower housing was cutting the heat even though it tested okay cold. Now I always do a live heat check before I call a part good. Anyone else run into a thermostat that only fails when it's hot?

3 comments

3 Comments

robert_ross957d ago

Honestly, that seems like a lot of extra work for a maybe... if a thermostat tests fine cold with a meter, it's good. You probably just had a weird one-off fluke. Most of the time, if the part specs out, you can trust your tools and move on to the next call.

alice9287d ago

Oh man, the classic "meter says it's fine" trap. I guess some parts just like to play dead until they get a little heat on them. Two minutes with a lighter sounds better than a whole extra trip back out.

lucast817d ago

Tell you what, robert_ross95, I've been burned too many times trusting a cold check. Had a Honeywell T87 last month that showed perfect continuity on the bench. Tossed it in hot water and the contacts just chattered, never made a solid connection. The meter said go, but the part was still bad. A quick heat test with a lighter or a cup of boiling water catches those ghosts. It adds two minutes and saves a callback when the customer says it's still not working right.