Is this a correct fresh-air setup?

Originally Posted By: Robert Horky
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I just purchased a house less then a month ago and I had it inspected. There is one aspect of the house I am kind of concerned about as time goes on and it deals with what I think is a fresh air intake for the furnace and hot-water heater. The setup is this. My 80+% gas furance and water heater are located in my walkout basement. There is a 12inch diameter metal HVAC pipe that runs from a vent outside the house to a pretty much dead stop near the furnace (it does a 90degree bend on the way down to the furnace). There is no fitting on the end of the pipe, it just stops. My home inspector said this was normal but I have never seen nor heard of such a thing before? I just wanted a second opinion?


Is this a fresh-air intake for the furance & water heater? If so, does this setup work well or should I run fresh-air in another way?

Thanks,


Originally Posted By: jpope
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I assume you are referring to “combustion air” rather than “fresh air.” It sounds as if the 12 duct is substantial enough for this purpose.


An easy confirmation (rather than measurements and calculations) is the flame pattern and color when the furnace and water heater are both operating at a normal capacity.

The pretty blue flame ![icon_cool.gif](upload://oPnLkqdJc33Dyf2uA3TQwRkfhwd.gif) like on your stove top is what you want to see. A heavy yellow flame is an indication of insufficient combustion air.


--
Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738

Originally Posted By: Robert Horky
This post was automatically imported from our archived forum.



jpope wrote:
I assume you are referring to "combustion air" rather than "fresh air." It sounds as if the 12 duct is substantial enough for this purpose.

An easy confirmation (rather than measurements and calculations) is the flame pattern and color when the furnace and water heater are both operating at a normal capacity.

The pretty blue flame ![icon_cool.gif](upload://oPnLkqdJc33Dyf2uA3TQwRkfhwd.gif) like on your stove top is what you want to see. A heavy yellow flame is an indication of insufficient combustion air.


Yes the flame on both are blue as expected. It looks so strange that this pipe just ends and is like 1-2 feet away from the furnace......


Originally Posted By: jpope
This post was automatically imported from our archived forum.



The combustion of the fuel will draw air from where ever it’s available. So long as the duct in the supply is not blocked, there should be no problem.



Jeff Pope


JPI Home Inspection Service


“At JPI, we’ll help you look better”


(661) 212-0738

Originally Posted By: Robert Horky
This post was automatically imported from our archived forum.



jpope wrote:
The combustion of the fuel will draw air from where ever it's available. So long as the duct in the supply is not blocked, there should be no problem.


Thanks for your help!


Originally Posted By: Blaine Wiley
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Many municipalities are now requiring outside combustion air because houses are built so “tight”. Your vent sounds just like that situation.


Originally Posted By: ekartal
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I see hook shaped vents on roofs of new construction. Is this a source of combustion air for high efficiency units?


Erol Kartal
ProInspect


Originally Posted By: kmcmahon
This post was automatically imported from our archived forum.



That’s referred to as a goose-neck, and yes they are icon_smile.gif



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