Adding length to 6" chimney

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Ant428

New Member
Jan 13, 2023
48
New York
Hello all. I'd like to increase my draft, and was thinking I'd add a length of chimney pipe to my chimney. The recommended minimum length for my stove is 16' , and I'm just hitting that. I'm having some trouble keeping flue pipe temps, and when I do get ripping, I'm only at 350. But if it's not cold enough outside, I barely keep 300.

The problem is, I believe I need to match the exact manufacturer of class A pipe. Is there a way to figure out what brand I have? I don't see any writing on the pipe.
 
Hello all. I'd like to increase my draft, and was thinking I'd add a length of chimney pipe to my chimney. The recommended minimum length for my stove is 16' , and I'm just hitting that. I'm having some trouble keeping flue pipe temps, and when I do get ripping, I'm only at 350. But if it's not cold enough outside, I barely keep 300.

The problem is, I believe I need to match the exact manufacturer of class A pipe. Is there a way to figure out what brand I have? I don't see any writing on the pipe.
Yes you will need to match the chimney. Post a few pictures of the chimney someone may recognize it.
 
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Yes you will need to match the chimney. Post a few pictures of the chimney someone may recognize it.
Thanks. Here are some pictures of the chimney.

[Hearth.com] Adding length to 6" chimney [Hearth.com] Adding length to 6" chimney [Hearth.com] Adding length to 6" chimney
 
Do you have a good picture of the cap?

Is the soffit material metal? The chimney pipe needs 2" clearances to combustibles all the way up.
 
Do you have a good picture of the cap?

Is the soffit material metal? The chimney pipe needs 2" clearances to combustibles all the way up.
The soffit is vinyl. So I guess that needs to be redone? It was like this when we purchased the house.
I attached pictures of the original cap. I replaced it with a universal one because the original was banged up.

[Hearth.com] Adding length to 6" chimney [Hearth.com] Adding length to 6" chimney
 
The cap looks pretty old. I don't see it in any modern class A catalogs. The pipe also has longer twist-locking tabs than modern pipe.
 
I was thinking supervent or metalbestos. I measure 7 7/8"
The mushroom cap is similar, but it looks more dated. Looking at the 2006 Metalbestos catalog the Tee height is shorter and the cap is more modern.
 
I have a new stove that requires minimum of 15' of pipe. I have 3' of black pipe inside, a 90 there goes through the wall, then a 90 that takes the class A just shy of 15' to the cap. I wonder if changing the black stove pipe to double wall will help with the draft?
 
I have a new stove that requires minimum of 15' of pipe. I have 3' of black pipe inside, a 90 there goes through the wall, then a 90 that takes the class A just shy of 15' to the cap. I wonder if changing the black stove pipe to double wall will help with the draft?
It's likely you are not getting secondary combustion in the stove. What is the make and model?

The two 90º turns in the flue path are effectively lopping off about 4 ft of chimney height. Double-wall stovepipe will help a little. So will changing out the 90º inside to a pair of 45s with an offset.

[Hearth.com] Adding length to 6" chimney
 
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It's likely you are not getting secondary combustion in the stove. What is the make and model?

The two 90º turns in the flue path are effectively lopping off about 4 ft of chimney height. Double-wall stovepipe will help a little. So will changing out the 90º inside to a pair of 45s with an offset.

View attachment 309326
I'm using a new Vermont Castings Dauntless. It's been a real hassle, lol.
 
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I'm using a new Vermont Castings Dauntless. It's been a real hassle, lol.
That is a bad combo for this setup. An easy-breathing stove would be less hassle.
 
Too late now. The dealer already sold it to me and I can't return it. Been having issues. Maybe a double wall pipe inside will help.
I doubt double wall will make enough of a difference
 
Sorry to hear you bought that V. C. Had an Encore 20 years ago. Ran fine for the first tree-five years and then was nothing but maintenance. I still like the US Stove barrel stove. Get the double and line the bottom third with fire brick. I got this Drolet Legend III and what a work out this has been....
Barrel stoves are unlisted and therefore you cannot do a new install of one in the US. Again if you want help getting your drolet to work properly start a thread and give us some more info. We can help
 
Too late now. The dealer already sold it to me and I can't return it. Been having issues. Maybe a double wall pipe inside will help.
I'm sorry to hear that. Most good dealers want a happy customer. Maybe they would take it in on a trade?
 
When it's cold out, and I have enough dry wood, it runs nice and temps are good. Flue temp only drops when it's all coals. Is that normal?
Yes that is normal sounds like you have almost enough draft it just looses it with warmer temps. So maybe double wall would be enough
 
Who installed it btw?
 
Who installed it btw?
Everything was pre existing. I had the stove delivered, and I installed the black pipe. I have a background in welding and fabrication, so I have the tools to cut and install the pipe. I just followed the guidelines in the manual.
The pipe through the wall and outside were all there when we purchased the house.

[Hearth.com] Adding length to 6" chimney
 
Everything was pre existing. I had the stove delivered, and I installed the black pipe. I have a background in welding and fabrication, so I have the tools to cut and install the pipe. I just followed the guidelines in the manual.
The pipe through the wall and outside were all there when we purchased the house.

View attachment 309336
I only asked because if the dealer installed it you would have some leverage to get them out to diagnose issues
 
I wonder if the single wall pipe heat shields like the link below, will help keep heat in the pipe and help with draft?

 
I wonder if the single wall pipe heat shields like the link below, will help keep heat in the pipe and help with draft?

No, that just reduces the clearances.