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Clint White
02-07-2009, 10:48 AM
http://i310.photobucket.com/albums/kk433/sihipro/013109-1021.jpg


Inspection from last week. New construction. Picture shows view from upstairs bathroom window (which is open). As you can see the vent stack for the gas furnace (TRANE XR90) is 6 - 7 feet from the window and approximately 1 foot below the level of the bottom of the window. I had the buyer with me at the time, and when we opened the window, you got a snoot full of exhaust. I called it as a safety issue, and the builder told me I was an idiot and that it met code. I don't care what the IMC says, this is just retarded.

I can just see the headlines...."Family leaves bathroom window open at night, furnace runs all night, family wakes up dead...Tonight at 11:00"

Am I out of line? comments?

Thanks
Clint

Jerry Peck
02-07-2009, 11:45 AM
I can just see the headlines...."Family leaves bathroom window open at night, furnace runs all night, family wakes up dead...Tonight at 11:00"

Am I out of line? comments?

Code or no code, you and your client got a first hand whiff of what that location is capable of, so, no, you are not out of line, well, except for this part ... "wake up dead" ... if they are "dead", they will not "wake up? ... :)

Richard Stanley
02-09-2009, 08:10 AM
Of course it's wrong.
Minimum 8' away or terminate above roof surface.
Go here for details www.askcodeman.com (http://www.askcodeman.com)

Jerry Peck
02-09-2009, 09:09 AM
Richard,

That's not a Type B gas vent, so you have to go by the manufacturer's installation instructions and not the code for Type B gas vents.

Yes, if that was a Type B gas vent, that would indeed by a problem, however, its location would not be the only problem, the vent material and type itself would be a problem. As would the lack of a Type B Gas Vent Cap, etc., there would be many things wrong.

Rick Hurst
02-09-2009, 10:22 AM
That looks like a sewer vent to me, not a furnace flue.:confused:

Was that area located over a laundry room or bathroom?

Ted Menelly
02-09-2009, 10:48 AM
That looks like a sewer vent to me, not a furnace flue.:confused:

Was that area located over a laundry room or bathroom?

Ditto

Jerry Peck
02-09-2009, 11:41 AM
That looks like a sewer vent to me, not a furnace flue.

That was my first thought too, because of the flashing, however, he did state:


As you can see the vent stack for the gas furnace (TRANE XR90)

So, I went with that.

If that is a plumbing vent terminal, then it needs to be 10 feet horizontally away from, or 2 feet vertically higher than, the closest portion of the operable window.

I figure it must be one of those high efficiency units which uses the power vent (condensing furnace?) instead of natural venting (with a Type B gas vent).

Rick Hurst
02-09-2009, 12:31 PM
I think the steam might have confused Clint thinking it was the furnace flue. Simple mistake.

rick

Richard Thacker
02-09-2009, 03:46 PM
All you must do is say to the builder, "The clients understand your position however their family lawyer is insisting that you provide written documentation that the vent proximity to the window does not pose a safety threat or health concern. Would you mind filling out an affidavit?"

Swear it works 80% of the time.:D

Clint White
02-09-2009, 06:10 PM
I actually did think this was a steaming waste vent at first. I saw it and then dismissed it as steam (it was 18 degrees outside).....then I realized that A.) the house was vacant B.) I had not run any water yet and C.) the water heater was off....thats when my curiousity was peaked and I opened up the window and WHEW did I get a face full. It was indeed exhaust fumes.

I traced the path of the pipe through the attic, yup it goes to the furnace. As far as the material type and lack of rain cap. It is very common in this area to install gas burning furnaces with DWV pipe and no cap. I have been told by most installers that the lack of a rain cap is ok due to the fact gas appliances produce so much condensation (which flows back down to the condensate tray)...a little more water isn't going to affect anything.

Clint

Brandon Whitmore
02-09-2009, 10:44 PM
It is very common in this area to install gas burning furnaces with DWV pipe and no cap. I have been told by most installers that the lack of a rain cap is ok due to the fact gas appliances produce so much condensation (which flows back down to the condensate tray)...a little more water isn't going to affect anything.


I know that it is common to not install an elbow/ cap, but what about debris that falls down the flue pipe?

Clint White
02-09-2009, 10:58 PM
Anything that falls into the pipe will eventually make its way to the condensate drain. These units produce an amazing amount of condensation because they remove so much heat from the exhaust, hence the use of plastic pipe as a muffler. As long as the exhaust pipe is properly pitched, the condensate will keep it washed clean. I guess in the event Manna falls from Heaven again, it might be an issue (joking)

I agree that there should be a turndown installed, but none, I mean NONE of the HVAC companies in my area do ????

Anyone else out there see this type of install (missing the macaroni on the end) ????

Clint

Richard Thacker
02-10-2009, 06:41 AM
The reason HVAC contractors don't install down pipes is because they will not climb on the roof after the roofer is done. It really is that simple.

Jerry Peck
02-10-2009, 07:18 AM
The reason HVAC contractors don't install down pipes is because they will not climb on the roof after the roofer is done. It really is that simple..

However, is it required by the manufacturer?

Getting back to the original question - what is the clearance from a window for those vent terminations?

I seem to remember that it was as little as 3 feet to 4 feet even when below a window - not that it matters, because, as I posted above "Code or no code, you and your client got a first hand whiff of what that location is capable of, so, no, you are not out of line,".

Daniel Leung
02-10-2009, 10:47 AM
Yes, it looks like a wet vent for sanitary sewers. Anyway, anything can be found. That is why the owner/buyer needs an inspector.

If it is a chimney in BC, it should be higher than the ridge of roof. See the attached PDF of BC Building Code 2006 (sorry, all in metric). Also, need laterally braced over 3.6m (~12').

To prevent making high stack on roof, most of the power vent of furnace in BC are going sideway, exhaust to the sidewall.

Jerry Peck
02-10-2009, 11:01 AM
If it is a chimney in BC,


Except it is not a "chimney" as shown in your drawings, it is a "vent", a "gas vent", which has different rules. And condensing furnace vents have even different rules, basically need the manufacturer's installation instructions to know for sure - unless you see and smell what is shown in that photo, in what case all you need is to see and smell it, then the answer is 'It needs to be relocated.' ... REGARDLESS what any code or manufacturer's installation instructions says - remember: *Codes and manufacturer's installation instructions are MINIMUMS.*

There are some examples in the code which are not "minimums" but finite requirements, such as: "handrail height is to be 34" minimum and 38" maximum above the plane of the nosings" - that is finite, between those two.

Most, however, are minimums, such as "guard shall be 36" high minimum", in which case you can make the guard 60" high is you so choose.

Other "minimums" are 'maximums', such as the "height of overcurrent devices shall be 6'7" maximum above the floor", unfortunately, there is no "minimum", so, yes, some electricians install them an inch above the ground, creating a new, non-code addressed, problem.

Code "minimums" (in the case immediately above, a "maximum") are for "minimum" life safety standards.

neal lewis
02-10-2009, 01:49 PM
[QUOTE=
If it is a chimney in BC, it should be higher than the ridge of roof. [/QUOTE]

Dan, that's not what it says. Only if the chimney is less than 3 meters from the ridge, does it have to extend above the ridge.

Daniel Leung
02-10-2009, 03:59 PM
Neal is correct, I wrote my previous words too short just for this case less than 3m.

More than the 4 drawings shown, the BC Building codes 2006 said:
9.21.4.4. Height of Chimney Flues
A chimney flue shall extend not less than
a) 900mm above the highest point at which the chimney comes in contact with the roof, and
b) 600mm above the highest roof surface or structure within 3m of the chimney.

As recommended by Jerry, we have refer to both codes and installation instruction from manufacturer. But the principals are the same - provide a safety living environment. If this vent is within 3m from the window, I think it shall extend over the window to prevent the smoke into house.

You know, nobody want to see a chimney/vent stacks in front of window. That is why the power vent outlets always take the shorter way to exhaust from sidewall in Vancouver, BC.

Another trend for the new house is using direct vent on sidewall to replace the roof chimney of fireplace. The builder avoid to make openings on roof to prevent leaking too.

Jerry Peck
02-10-2009, 07:54 PM
Another trend for the new house is using direct vent on sidewall


Yes, but with some of the new subdivisions sticking houses on top of one another, there may be restrictions as to how close that termination is allowed to be to a property line.