Chimney Liner options

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Maj92az

New Member
Sep 26, 2020
50
N Idaho
New home to me has a charmaster wood furnace in the basement. Its chimney has minor cracks along the way. Mostly near the top. 30ft. My quote is 4500. 2000 of it says 100ft of knockout. Not sure what that is.

I have heard many do the stainless insert themselves. My concern is the bottom. The furnace sits 3ft away from basement wall. 8" ducting then Ts into chimney with a clean out below.

Can a stainless liner/tube not be bent and connected to the furnace ducting? A T seems like it would be tight to get in there and work with. The chimney flue is all within the foundation and chimney below grade. The clean out would then become obsolete.
I assume that's the knock out to get into the work area. Any advice here?
 
Knockout may be them removing the existing clay liner...which would need to be done if the flue is too small to get a liner in...especially with the proper insulation on it...not sure why 100' is quoted.
The liner doesn't bend around the corner...the tees that are made to go on the bottom of the liner are 2 piece and made to work within the confined spaces of a chimney...I had mine crimped on the bottom so that I could put a flex liner extension on the bottom of it, so I can still use my cleanout door...I just put a cap on the bottom of the extension and then slide a brick under it to hold it on.
There are lots of how to videos that show how to DIY a liner, and you can also see how the tee system works.
 
Thank you. After further searching I found the product that possibly would work- the two peice tee, with the looped hose clamp for lack of proper term...and they come with that cap- that brick (properly sized) would be a good idea! Do all the joints that use clamps get sealant or if properly clamped, none needed?

Its certainly all new to me. The sellers of the home left me $1250 for it. They certainly helped many other ways so I was happy with something. But.. I will call the company that quoted the knockout and ask more questions on why...and if 100' was a typo.

I will need to research on the proper size.. and determine if insulation is necessary. The thimble enters out the basement wall (foundation) and enters the chimney which is right there at the end of the home. No combustible material.
 
No sealant needed if done properly.
I think a Charmaster uses an 8" flue...if so, that's what size the liner needs to be.
One tip, don't buy 2 ply (or "doublewall") liner, also called smoothbore, or some variation of...nothing but problems. Standard single wall SS liner is fine...or if you want HD, buy HD single wall, or HD "single ply".
Insulation will help the liner stay cleaner, and draft better, not just for CTC...which its hard to know 100% for sure that there is no combustibles tied into the chimney...its more common than you would think...insulation is almost always worth the time and expense to do.
 
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Ok thanks. I will begin looking for kits soon. I have not fully moved in and the home is 2 hours away. This week I'll be living there full time and I'll dedicate time to thoroughly examine and take pictures of what we are doing with. I'm sure I'll be posting a few questions on the process. But it seems kinda straightforward as long as I take my time and do quality work and mostly importantly listen to advice.

Is there a favorite website that will sell me everything?
 
Talked to the quoting company..100ft knockout was accurate..its a standard 6×10 ID opening. They are telling me 8" will not fit...must remove tiles and add liner. Is that true?? 6x10 is 60 sq in and 8" is about 51". Is an oval not an option?

Another option (not any easier) is demolish the chimney and install rigid metal chimney. The chimney has had mentions of not being in great shape...pics in a few days.
 
Talked to the quoting company..100ft knockout was accurate..its a standard 6×10 ID opening.
100 square ft?
Yeah, 8" is probably very unlikely to go into a 6 x 10
 
Talked to the quoting company..100ft knockout was accurate..its a standard 6×10 ID opening. They are telling me 8" will not fit...must remove tiles and add liner. Is that true?? 6x10 is 60 sq in and 8" is about 51". Is an oval not an option?

Another option (not any easier) is demolish the chimney and install rigid metal chimney. The chimney has had mentions of not being in great shape...pics in a few days.

If the chimney structure itself is not in good shape, that could be your decision maker. Or made for you. But if it wasn't - they should have advised of that?

But yes, if relining I would knock the clay out.
 
Even with removing the clay you will probably need to ovalize in order to insulate