Pipe size?

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Deiswerth

New Member
Nov 27, 2021
16
Pa
Questioning what size pipe I should have from the back of my wood stove to the chimney. The back of my stove is 7". I put a stainless steel liner in my chimney, 6". What size should I use going to the liner? Neck it down at the stove to 6" or run 7" to where it goes through the wall and my 6" liner begins? Coming from the stove it consists of 2 90° and about 36" of pipe. Thank you!
 

begreen

Mooderator
Staff member
Nov 18, 2005
93,201
South Puget Sound, WA
The two 90º turns are adding restriction. Would it be possible to reduce this, maybe by using 45s? What stove is this for?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
Questioning what size pipe I should have from the back of my wood stove to the chimney. The back of my stove is 7". I put a stainless steel liner in my chimney, 6". What size should I use going to the liner? Neck it down at the stove to 6" or run 7" to where it goes through the wall and my 6" liner begins? Coming from the stove it consists of 2 90° and about 36" of pipe. Thank you!
Well the liner should have been 7" to match the stove. But at this point it really doesn't matter where you reduce it.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
7" wouldn't fit down the existing flue
Then the clay tiles needed removed. How did you fit insulation with the old liners in place?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
Didn't know it needed insulation...
Does your chimney have the required clearance from the outside of the masonry structure to combustible materials?
 

Deiswerth

New Member
Nov 27, 2021
16
Pa
Does your chimney have the required clearance from the outside of the masonry structure to combustible materials?
Not exactly sure what you mean by this??? It's and exterior block chimney, with terracotta liner, stainless steel liner...how much more do I need to be away from combustible materials???
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
Not exactly sure what you mean by this??? It's and exterior block chimney, with terracotta liner, stainless steel liner...how much more do I need to be away from combustible materials???
1" between the outside of the block and combustible materials.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
If the chimney was internal it would need 2"
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
I mentioned it was outside....external....was just a question about pipe size...
And I gave you an answer on the pipe size along with other pertinent information.
 

snobuilder

Feeling the Heat
Dec 16, 2021
431
WI
Questioning what size pipe I should have from the back of my wood stove to the chimney. The back of my stove is 7". I put a stainless steel liner in my chimney, 6". What size should I use going to the liner? Neck it down at the stove to 6" or run 7" to where it goes through the wall and my 6" liner begins? Coming from the stove it consists of 2 90° and about 36" of pipe. Thank you!
Looks like you ran into a chimney condescension problem.
Best of luck.
Hang in there.
 
Last edited:

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
Looks like you ran into a chimney condescension problem.
Best of luck.
Hang in there.
I was simply trying to tell him the proper way it should be done. And trying to make sure the setup is safe. No condescension.
 

begreen

Mooderator
Staff member
Nov 18, 2005
93,201
South Puget Sound, WA
Harmon stove. Don't know if I have enough room to get 4 45° in...
Which Harman model? All those that I have records for are 6", but I don't have every manual. Can you post a picture of the installation location and a sketch of the proposed stovepipe layout. Usually there is a way to eliminate at least one 90º elbow.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
28,466
central pa
Which Harman model? All those that I have records for are 6", but I don't have every manual. Can you post a picture of the installation location and a sketch of the proposed stovepipe layout. Usually there is a way to eliminate at least one 90º elbow.
Some of their wood/coal stoves were 7" I think the mark III