Monday, November 26, 2012

Misfiring Furnace

So, The colder weather is upon us.

My House is an Old(ish) one, and I'm fairly sure the furnace only has a few years left on it.

I noticed, that sometimes, it fires up, turns off immedately, and then fires up again, and stays on, heating my house.

There is a little sensor inside your furnace, that makes sure that there is a fire inside. If this sensor doesn't detect fire, it shuts off the gas immedately.


if it kept spewing gas into the furnace, with no fire, you could potentially have an explosive situation on your hands. And considering you're still getting comfortable in your new house... having your basement blow up on you isn't the most ideal situation.

So I cranked up the heat and ran down stairs. Sure enough, on the first attempt - there WAS fire. But it shut off anyway.

After much googling (5 minutes is an eternity to someone as impatient as me) I figured out the issue.

That little sensor, had collected up a lot of Carbon/soot and dirt on it. Insulating it from the heat a bit. As a result it was telling the furnace that the party hadn't started yet, and to shut the gas off.

It was easy to fix. I stupidly didn't document it, but I followed this youtube video to a T, and it was perfect in helping me.

Basically, taking this sensor and sanding it clean fixed my issue. Yay for saving myself a few hundred dollars!


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