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Smell gas through vents when furnace is running

I noticed this year when I turned on our heater that there was a natural gas smell coming through the vents. Alarmed I asked my husband to check it out. He seems to think that it is just not "burning off" that it is just the smell, not really the gas itself. i would really like to know!!

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Re: smell gas through vents when furnace is running

I would strongly suggest a carbon monoxide detector first. Also your gas provider should do a free leak check. This is nothing to play with.

Posted on Dec 04, 2007

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I have in Intertherm gas furnace. The system runs, hot air comes out of the vents, but it smells like burnt plastic, and the red light on the circuit board is lit up...

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It appears only one of the three burners are burning, ther is also the smell of unburt gas coming from the furnace vent. it's a Payne Plus 90 condensing furnace

Check to make sure your roof vent cap has not come off. This will cause this to happen. If its there, shut unit off, and pull out the burners that are not working. Just push forward and tilt the back end up to remove them. Turn them over and tap the rust and dirt from them. Reinstall them. Make sure they are in place right. This will solve your problem. This is why you smell raw gas.
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Annoying undetectible odor from HVAC vents.

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