Temperature decrease/Flu pipe length

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Maringotka

New Member
Nov 23, 2018
17
23027
It seems logical to me that the temperature of the pipe at the top of the chimney would be less than the temperature of the pipe where it connects to the stove.

If that’s true then, if the distance from the stove to the ceiling is great enough, there would be no need for anything more than an air space around the thimble the passes through the combustible 2 x 4 vaulted ceiling.

True?
 
If you have a chimney fire it'll get plenty hot up there.
 
It seems logical to me that the temperature of the pipe at the top of the chimney would be less than the temperature of the pipe where it connects to the stove.

If that’s true then, if the distance from the stove to the ceiling is great enough, there would be no need for anything more than an air space around the thimble the passes through the combustible 2 x 4 vaulted ceiling.

True?

How do you propose totally surrounding a thimble with an airspace?
 
It seems logical to me that the temperature of the pipe at the top of the chimney would be less than the temperature of the pipe where it connects to the stove.

If that’s true then, if the distance from the stove to the ceiling is great enough, there would be no need for anything more than an air space around the thimble the passes through the combustible 2 x 4 vaulted ceiling.

True?
You need to use a listed chimney system to do this. Yes the temps will be lower but they have to stay above the condensation point or you will have lots of creosote buildup and huge risk of chimney fire
 
In a tiny house you will still need to do things properly. If the flue is going thru the roof then you will need a short cathedral ceiling support box. This will support the chimney pipe and assure proper clearances. Depending on the roof pitch and exit location you may be able to get away with just a single length of chimney pipe. It's common to hook the F602 up with 6" round stove and chimney pipe.

Here is a video illustrating the installation in a tiny house. He makes some mistakes. There must be 2" clearance from the chimney pipe. His does not have that. And this is with a metal roof and with a 4" pipe system. A composition roof install and flashing are different with the support box top folded to make a flange on the roof. But it will give you an idea of installing.

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FWIW, the cap system for this chimney pipe seems excessive.
 
Last edited:
If you have a chimney fire it'll get plenty hot up there.

Yep, that is the real kicker... the specs and requirements aren't really written with normal operation in mind. You have to build it for that one SHTF day when the flue is on fire and glowing red hot.
 
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Dickerson thimble
[Hearth.com] Temperature decrease/Flu pipe length
How do you propose totally surrounding a thimble with an airspace?
 
In a tiny house you will still need to do things properly. If the flue is going thru the roof then you will need a short cathedral ceiling support box. This will support the chimney pipe and assure proper clearances. Depending on the roof pitch and exit location you may be able to get away with just a single length of chimney pipe. It's common to hook the F602 up with 6" round stove and chimney pipe.

Here is a video illustrating the installation in a tiny house. He makes some mistakes. There must be 2" clearance from the chimney pipe. His does not have that. And this is with a metal roof and with a 4" pipe system. A composition roof install and flashing are different with the support box top folded to make a flange on the roof. But it will give you an idea of installing.

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FWIW, the cap system for this chimney pipe seems excessive.



Thanks for the video. This installation is for a pellet stove?
 
Dickinson marine




The product that you have indicated would definitely allow you to mate a 5" pipe with another 5" pipe as well as allow for safe clearance while going through the roof. There is no need for added insulation as you would cut a 7" hole for the 5" pipe. The gap is to allow for air circulation and to prevent heat transfer from material to material.


Kind Regards,


Jeremy Edgar

Dickinson Manufacturing

Dickinson Marine/ Sig Marine

101-17728 66th Ave

Surrey, BC V3S7X1 Canada

Tel: 604-574-8641

Fax: 604-574-8659

www.dickinsonmarine.com
 
Dickinson marine




The product that you have indicated would definitely allow you to mate a 5" pipe with another 5" pipe as well as allow for safe clearance while going through the roof. There is no need for added insulation as you would cut a 7" hole for the 5" pipe. The gap is to allow for air circulation and to prevent heat transfer from material to material.


Kind Regards,


Jeremy Edgar

Dickinson Manufacturing

Dickinson Marine/ Sig Marine

101-17728 66th Ave

Surrey, BC V3S7X1 Canada

Tel: 604-574-8641

Fax: 604-574-8659

www.dickinsonmarine.com
You do realize the required clearance from single wall pipe to combustibles is 18" not 2" right????
 
Dickinson marine




The product that you have indicated would definitely allow you to mate a 5" pipe with another 5" pipe as well as allow for safe clearance while going through the roof. There is no need for added insulation as you would cut a 7" hole for the 5" pipe. The gap is to allow for air circulation and to prevent heat transfer from material to material.


Kind Regards,


Jeremy Edgar

Dickinson Manufacturing

Dickinson Marine/ Sig Marine

101-17728 66th Ave

Surrey, BC V3S7X1 Canada

Tel: 604-574-8641

Fax: 604-574-8659

www.dickinsonmarine.com

Did Mr. Edgar have a full understanding of what you were intending to do with it? And where?

Not likely, based on all the threads started that seem to be hinting around for a solution without full disclosure of what the situation is.
 
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