HVAC Question

[bushman]

I have a quick question for all you HVAC guys. I have been noticing an odd smell comming from my furnace stack, outside my house. I have an old natural gas furnace. I only smell the odor when the furnace is running and i don not smell it inside. I have a CO alarm and a Gas alarm and neither have sounded. Any ideas as to what this could be? Is this something that requires imidiate attention? Thanks in advance.

Dave

 

[blake]

I know nothing about your system. But I would get it checked out ASAP....think SAFETY!

 

[crash]

hard to say , bushman depends on type of furnace need make model , 70%, 80%, 90% could be belt , blower motor, 2nd heat exchanger plugged, any gas work done in area ? gas valve malfunction, kids drop something down the duct work ? central Iowa know`s alot about that kind of stuff may want to send him an e-mail may want to have a co2 test preformed on your furnace, even though your alarm doesn`t go off you still could have a crack in the heat exchanger. could have a dead animal stuck in your chimney, it happend to my dad. (coon)hope this help`s

 

[bushman]

I believe it's rated like a 60% or 70%. Some gas work done next door, they had a leak in their house. I asked, they said it wouldn't effect me. I doubt any kids dumped anything, it's on the roof. Thanks for the advise.

 

[tracker]

IF it was a LP furnace and you just recently noticed the smell then you could possibly be out of gas in your tank. When the LP furnaces are running on empty the flame doesn't burn HOT enough to burn up the whatever it is stuff they use to put an odor in it. Sorry can't help out on natural gas...

 

[Central Iowa]

Good info already posted. Don't mess around, get it checked. I'm sure for under a hundred bucks you can get it figured out.

 

[strutnrut]

You might have a heat exchanger that is some what plugged. If you can look at the burners, see if they look like they are burning nice and clean. ( blue flame) usually lp is the worst for this problem but I have seen on a few natural gas furnace do the same. JUST BE SURE TO HAVE A PROFESSIONAL CHECK IT OUT!!!!!! If it is only 60-70 % eff. you need to upgrade to a higher eff. furnace anyway.. your furnace is 25 plus years old.

 

[bushman]

thanks for all the help guys, had a guy out last night, high CO level in the stack, only 2 ppm in the room but i'm glad i had them out. Now the only trouble is finding an in stock furnace to get installed today. Thanks again for all the input.