Maximum single wall connector length?

[mikeathens]

Never been a factor for me since I've never had a cathedral ceiling, but I'm putting an addition on my house this summer, and both my Mansfield and Heartland Sweetheart cookstove will be going though a cathedral ceiling.

When installing my first chimney about 8 years ago, I thought I had remembered reading a "maximum" conector pipe length, at which point you had to use double-wall class A. But I can't seem to find anything now.

Can anyone point me in the right direction? For one stove, the ceiling will be about 14 feet above the flue collar, and then 3 feet of double wall chimney above the roof. For the other, the ceiling will be about 8 feet above the collar, with an additional 3 feet of double wall chimney above the roof. Just trying to do some planning...

 

[Nic36]

I have seen it here and there, but the only place I remember where was in an Englander stove manual. It says that "Single wall flue pipe assemblies must not exceed 10 feet in overall length."

http://www.englanderstoves.com/manuals/30-NC.pdf (Page 12)

I don't know if that is specific for that stove or a general rule.

I would say with the 8' you would be fine using single wall, but the 14' would have to be double wall.

 

[fossil]

Mike, Class A pipe is chimney pipe...specifically for use after penetrating the wall or ceiling. Connector pipe (or stovepipe) is for use from the stove flue collar to the transition to Class A. There is never a requirement to use Class A inside the living space. Connector pipe comes single-wall and double-wall. If a stove manufacturer specifies a maximum run length for single-wall connector pipe, my guess is that the concern is maintaining flue temperature. If I had such a stove and had to exceed the recommended run length, I'd just use double-wall connector pipe from the stove to the Class A chimney transition. My Lopi Liberty has a vertical run of ~14' of single-wall to reach the transition at the cathedral ceiling. Professionally installed, permitted, and inspected. Works just fine. I might swap it out for double-wall next year anyway, just so I feel better about the flue temps. Rick

 

[DAKSY]

I've never seen a stove with a maximum single-wall connector limit, & I haven't seen a double-wall that will connect
to a single wall. For the most part, you hafta use one or the other until you get to the first penetration - Wall OR Ceiling -
& from there to the cap it has to be Class A Chimney

 

[Nic36]

Sorry, I missed the part about you saying double wall "Class A". I need to read better. I was referring strictly to double and single wall stove pipe and not Class A chimney.

 

[begreen]

In reference to single wall installations the VC Encore manual states:
The recommended maximum length of a horizontal
run is 3’ (1 m), and the total length should be no longer
than 8’ (2.4 m). In cathedral ceiling installations, extend
the prefabricated chimney downward to within 8’ (2.4 m)
of the stove.

Hearthstone (Heritage) makes this recommendation:
Long runs of stovepipe to increase heat dispersal are not
recommended. Using longer lengths of stovepipe or more
connecting elbows than necessary increase the chances of
draft resistance and the accumulation of creosote buildup.

 

[mikeathens]

In reference to single wall installations the VC Encore manual states:
The recommended maximum length of a horizontal
run is 3’ (1 m), and the total length should be no longer
than 8’ (2.4 m). In cathedral ceiling installations, extend
the prefabricated chimney downward to within 8’ (2.4 m)
of the stove.

YEAH, BG!! That's it! I must have read that in my Dutchwest Catalytic manual way back when. I had never seen any type of "extension" or support package that would allow the beginning of the class A in the living space, though? How would one do this with a 18' high ceiling? Selkirk's cathedral ceiling support only extends the prefab into the living space by a foot or so.

I guess this would be a good time for me to replace all of that single-wall with double wall connector, anyway.

 

[begreen]

I had never seen any type of "extension" or support package that would allow the beginning of the class A in the living space, though? How would one do this with a 18' high ceiling? Selkirk's cathedral ceiling support only extends the prefab into the living space by a foot or so.

A roof bracket supported system is what I'm guessing they're referring to.

 

[Darl Bundren]

I had never seen any type of "extension" or support package that would allow the beginning of the class A in the living space, though? How would one do this with a 18' high ceiling? Selkirk's cathedral ceiling support only extends the prefab into the living space by a foot or so.

The Duratech roof support will support 20' of chimney below the roof support, so I reckon if you wanted to you could bring it down a ways.