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Jon mackay
04-30-2009, 08:57 AM
I came across a Trane Furnace that had an unusual routing for the fresh air intake and exhaust.

The fresh air intake was routed toward the rear of the house and now has a very low deck installed at this area. I am assuming that the air intake should be re routed to a more suitable location but could not find specs for this. The picture shows the decks low height.

Also, the exhaust vent is routed to the right side of the house which I thought to be unusual as all the installations that I have seen before exit the house at the same approximate location. The exhaust is also close to the gas meter which I believe may not be allowed, see picture

Jerry Peck
04-30-2009, 09:01 AM
Yikes!

You do not want EITHER that fresh air intake (and exhaust if direct vent) OR that disconnect ... THAT close to the gas meter (goes for that a/c unit to the left too!).

And, if that window opens, I'm not even sure the gas meter is allowed that close (I recall the distance being 3 feet from a building opening).

Jon mackay
04-30-2009, 10:16 AM
The exhaust is a pvc from a high efficiency system so more moisture than anything.
The air intake under the deck I'm thinking would be a good thing to re route.

Scott Patterson
04-30-2009, 10:27 AM
The exhaust is a pvc from a high efficiency system so more moisture than anything.
The air intake under the deck I'm thinking would be a good thing to re route.

Actually they produce as much CO as a conventional furnace, the flue gas is just not "hot" and the CO tends to not dissipate as much with this type of furnace.

A.D. Miller
04-30-2009, 11:41 AM
I came across a Trane Furnace that had an unusual routing for the fresh air intake and exhaust.

The fresh air intake was routed toward the rear of the house and now has a very low deck installed at this area. I am assuming that the air intake should be re routed to a more suitable location but could not find specs for this. The picture shows the decks low height.

Also, the exhaust vent is routed to the right side of the house which I thought to be unusual as all the installations that I have seen before exit the house at the same approximate location. The exhaust is also close to the gas meter which I believe may not be allowed, see picture

John:

JP is correct about the 3'-0" clearance to building openings. That includes fresh air intakes, windows, doors, et al.

Jerry Peck
04-30-2009, 11:50 AM
Aaron,

Don't forget the a/c condenser unit, it would be equivalent to the electrical meter on your drawing - it is an automatic ignition device, switching on and off automatically.

Yes, that includes that air intake, which is actually worse than just an opening as it is forcibly drawing air in, makes one want to give something like that even more clearance.

A.D. Miller
04-30-2009, 12:21 PM
Aaron,

Don't forget the a/c condenser unit, it would be equivalent to the electrical meter on your drawing - it is an automatic ignition device, switching on and off automatically.

Yes, that includes that air intake, which is actually worse than just an opening as it is forcibly drawing air in, makes one want to give something like that even more clearance.

JP: I can't find specifics on that idea. IRC defers to the DOT for meter placement. All I can find from them is at:

http://www.phmsa.dot.gov/staticfiles/PHMSA/DownloadableFiles/Files/7%20-%20Guidance%20Manual%20for%20Operators%20of%20Smal l%20Natural%20Gas%20Systems-2002.pdf

What else do you have?

Kyle Smith
05-01-2009, 10:03 AM
The furnace manual would really help. Usually you need at least 3 feet from the service and a foot above a fully open deck.

Eric Barker
05-03-2009, 06:22 PM
The furnace manufacturer's specifications are the ONLY specs you should follow. Generic diagrams for through wall venting guidelines are nothing more than that and can be wrong for many installations.

Mike Schulz
05-05-2009, 02:44 PM
JP is correct about the 3'-0" clearance to building openings.
Picture to me is a little confusing. What is the 8" clearance next to the window for? I assume the other 8" one to the right is for cable, phone, etc.