Chimney Liner upgrades

[JA600L]

Hello guys,
I stopped in at DS Stoves machine shop here in Lancaster and discussed options to upgrade my chimney to an insulated liner. Right now it has a 25 ft single ply liner installed in a 7x11 terra cotta outside chimney. They game me 3 routes that I could possibly take after they look at it.

1. Remove the liner, bust out the Terra cotta, wrap the liner in insulation, and reinstall it.
2. Install an ovalized liner with insulation wrapped around it.
3. Drop pour in insulation into the cavity between the liner and Terra cotta and get it as good as possible. Not the best option, but probably better then what I have now.

Their main concern was with with my chimney housing 3 flues. They are not sure if there is a good masonry wall between flues. They don't want to bust out the Terra cotta if there isn't. They did not come out and look at it yet.

I'm tempted to let them do the pour in if they can't bust the Terra cotta. I would absolutely like to bring it up to code if possible. They only charge $175 to bust out the Terra cotta so that is my #1 right now. Any thoughts?

 

[bholler]

I'm tempted to let them do the pour in if they can't bust the Terra cotta.

That will not get you to code but yes it will improve the performance

Their main concern was with with my chimney housing 3 flues. They are not sure if there is a good masonry wall between flues. They don't want to bust out the Terra cotta if there isn't. They did not come out and look at it yet.

Yes that is a major concern. we always inspect very carefully in cases like that. If you go that rout make sure you know what will happen if they damage another liner in the process. ovalizing is not a bad option
.

 

[JA600L]

So in other words, the cavity around the three flues could be hollow?

Let me ask you this. If I take all other options off of the table, and let them pour in insulation, will it be worth the effort and cost?

Can the liner I currently have be ovalized or would I need to purchase a new liner?

 

[bholler]

Let me ask you this. If I take all other options off of the table, and let them pour in insulation, will it be worth the effort and cost?

It will be worth it unless the liner is to close to a wall of the chimney which then transfers heat through to an adjacent combustible material and it catches fire. The chances of that are pretty slim but it is possible.

Can the liner I currently have be ovalized or would I need to purchase a new liner?

That depends on a few things. One is call woodstock and ask them if the stove will be ok with the reduced volume of an ovalized liner. Next would be if your installer has an ovalizer. I would not let them do it unless they have the proper equipment. Just smashing it generally does not work out very well.

 

[JA600L]

I don't know if it really makes a difference or not, but the 11'' stretch of the flue runs with the direction of the house. That means that the liner is centered and not as close to the house side of the flue. Since I am heating from the block wall basement, there is a brick hearth on the main floor above it that does have an air space behind it. Still not ideal, but hopefully that makes the situation better.