Install: through wall with pipe seam

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Jordan

Member
Apr 25, 2018
52
emmett, idaho
Installing Class A through wall. Can you have a seam between the wall? To get my measurements to work with the stove and outside wall bracket I could use a 12" and 6" pipe. That would leave the seam in the wall.

Didn't account for the 3" required to the inside. Was planning on 1".

For some reason the seam in the wall freaks me out but it shouldnt if its safe on the outside.
 
By seam do you mean the connection between the (2) class A pipes? How thick is your wall your going through?
 
By seam do you mean the connection between the (2) class A pipes? How thick is your wall your going through?

Thats' precisely what I mean. Seam between the pipes in the wall sleeve. Naturally it would have a locking clamp.

Wall is 10" thick but the Class A Chimney pipe manual says I need a minimum 3" inside the house. Add the minimum 2" to the outside makes for a total of 15" of pipe. I can only get 6, 12, or 18 inch sections but with the male side it subtracts an inch. So if I add a 12 and 6 it makes for 16" which is workable with the outside support adjustment. If I go with the 18" Im forced to install the outside bracket an additional 4 inches from the house.

If I could install 1" inside the house then 12" might work but that would be against the installation requirements.
 
Why not run a 18” and just adjust the black pipe and stove to fit? Unless hearth room is an issue
 
We use telescoping sections of chimney pipe there but many chimney manufacturers don't offer that. If you can't get telescoping I would just use an 18 and have it stick through the wall a little more.
 
I'm trying to keep the stove as close to the wall as possible since its not a large room. I would have done a telescoping class A like ICC offers but they're not allowed in through wall applications. At least not for ICC.

So do you think the seam in the wall thimble is safe?
 
I'm trying to keep the stove as close to the wall as possible since its not a large room. I would have done a telescoping class A like ICC offers but they're not allowed in through wall applications. At least not for ICC.

So do you think the seam in the wall thimble is safe?
It is allowed with ventis.
 
I am just going by observation, but the ends of some class A has solid stainless ends. That will transfer much heat from the inside to the outside at the joints. Some brands have open ends with just a small connection of stainless and the insulation is exposed so that less heat is transferred. I personally would keep the joints in an open air environment and not contained in walls or support boxes etc. Do as @kennyp2339 says and use a longer piece and adjust your stove set from there.
 
I'm trying to keep the stove as close to the wall as possible since its not a large room. I would have done a telescoping class A like ICC offers but they're not allowed in through wall applications. At least not for ICC.

So do you think the seam in the wall thimble is safe?

Where did you read this as the Canadian icc excel manual suggests a short length with the telescoping length off the snout of the tee for horizontal through the wall applications.
 
Where did you read this as the Canadian icc excel manual suggests a short length with the telescoping length off the snout of the tee for horizontal through the wall applications.

The manual I have says the telescoping section is to not be attached to a Tee.
 
The manual I have says the telescoping section is to not be attached to a Tee.

That’s because it can’t adjust into a tee it would block the flow, you need to attach a length of 6” 12” etc to the tee than attach the telescoping pipe to that so it can adjust into it.
 
Thats good to know about the adjustable pipe. Didnt understand thats how it works.

I called the manufacturer about having the seam in the wall thimble. There technician called me back and said thats perfectly fine. Said the seam is lowest temp spot on the pipe. The seam is apparently the most insulated point and if theres air leaks it sucks air in causing even less heat.
 
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