Furnace Kicks On and Off and On and...

While working in the garage yesterday, I noticed that my furnace is cycling on and off *constantly*. I hear the gas jets kick on and they burn for about 15 seconds, then shut off. About 30 seconds later it repeats the process, over and over and over again. Only occasionally did the blower kick on where hot air was pushed through the house.

I don't know a dang thing about furnaces, but this can't be normal functioning of the furnace, can it?

-F

Reply to
Fleemo
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Nope. Not normal. If you know nothing of furnace repairs call a reputable repair company. It could be one of several things, but most likely a bada thermo-couple fo some sort that is causing the burner to shut down before the blower comes on. I'd get it looked into before the really cold weather hits!

Reply to
mwlogs

Maybe a flame rectification problem....

Reply to
HeatMan

Nope, definitely not normal. Could be a number of things (bad flame sensor among them).

Here is some troubleshooting help -- however, gas isn't something for the untrained DIYer to mess with. I'd recommend you call a professional.

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Reply to
Travis Jordan

Hi, How about starting with your furnace model? Tony

Reply to
Tony Hwang

Not enough info to even begin to tell you where to look, but as others have suggested, if you are not familiar with the operation and sequence of proper events, call a company, and make sure they are licenced and insured.

Reply to
steve

snipped-for-privacy@comcast.net (Fleemo) wrote in news: snipped-for-privacy@posting.google.com:

Mine was doing that. It was the thermostat doing it.

Reply to
TaskProperties

There is a long list of possible causes. The least likely of all of these is the thermostat.

Gary R. Lloyd CMS HVACR Troubleshooting Books/Software

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Reply to
Gary R. Lloyd
041121 1403 - Fleemo posted:

In general, there are two limit switches in the furnace plenum: the fan limit, and the gas solenoid high heat limit. It is obvious, in your case, that the fan limit is set too high and the heat in the plenum is rising above this setting to a point that the gas valve high limit is tripping the gas valve closed. When it cools, it turns the gas valve back on again and this cycle repeats. Find the fan limit and set it lower, maybe around 140 degrees and see if that will make a difference. From your description, it is obviously not the room thermostat. If you cannot change the settings on the fan limit switch, maybe it is broken and needs replacing.

Reply to
indago

Hmm. If you rectifier, that mean you put it out? (say it slow: Wrecked the fire)

Reply to
Stormin Mormon

Boy, you ain't got a clue.

If you were truing to be funny, you missed.

Reply to
HeatMan

Sad part is that Chris was serious, and I really hope NO ONE in here is taking anything hes got to say serious...

In these parts, he would have already been arressted for contracting without a licnece.

Reply to
steve

Here too.

Except it would have been a license....

Reply to
HeatMan

typos....typos...

Reply to
steve

if that will make a difference.<

Anywhere online where I might see a photo or diagram of what the fan limit looks like? I'd rather attempt a simple fix first, and if that doesn't work, wait ten days for a pro.

Reply to
Fleemo

Heatman, unlike you Chris, knows what he is talking about and in this case, you are wrong, and hes right...about the term used...

Dumbass is too nice a term for you.

Say it slow...dum ahssss

Reply to
steve

Looked it up...limited support from Carrier.

Depending on your part of the country, thats normal for this time of year... Also, since the election, this trades business has taken off for the better companies.

and you should, since if you dont know what it looks like, or even if you have one, you can create more damage than you have now. Not all of those old Carrier/Payne units had them. Particularly since the blowers were on timers that were hardwired into the controls.

Depends onthe thermostat you have. While the least likely item would be the stat, its possible you are #10, and 9 out of 10 issues are not the thermostat, perhaps your numbers up. Wait a bit, get the tech to check it.

Reply to
steve
041124 0315 - Fleemo posted:

Check this out for starters...

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Reply to
indago

You on drugs or something?

Reply to
HeatMan

Not really...I dont do that shit. Dont drink either...but Chris has to be on them...

Reply to
steve

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