No Mortar in Clay Flue

[mykullshepherd]

Hello!

I am relatively new to wood burning having just moved into a home a few years ago that has two wood burners in it and have been learning a lot as we go. This site has been a wealth of knowledge, and from what I have been reading I think I already know the answer but thought I would post my predicament anyway for confirmation.

One of our chimneys is masonry with a clay liner that runs three stories from the basement to the top of the two story house. We have it connected to a freestanding Enviro Kodiak 1700 stove. The chimney and the house are about 19 years old.

Long story short this summer while repairing a mortar joint on the exterior of the chimney and repairing some cracks in the cap I discovered that the clay liner tiles are not mortared to one another. I can literally reach down in the chimney and move the top few tiles. It is clear there is no mortar at all. Looking further down I can see that most tiles are sitting a little offset of one another all the way down.
We have been told that the local Amish originally built our house - which explains a lot of things we have discovered and may explain this as well.

So I am assuming I should be installing a stainless steel liner to make this situation safe? The clay tile is 6"x10" on the interior and the stove requires a 6" flue. I imagine a 6" round liner would be nearly impossible to pull down through three stories, so I am thinking an oval liner such as a 5"x9" or so that has equal or more area of the 6"?

Any suggestions or insight would be appreciated.

Thanks

Michael

 

[kennyp2339]

Is there anyway you can test your draft on the existing chimney, I'm thinking that if you go with an 6" oval liner you may create an excessive draft (3) stories of 36ft. You may need to go with a larger liner to slow things down some.

 

[bholler]

Yes you need a stainless liner. But i would remove the clay liners and put in a 6" insulated liner. You will probably need a pipe damper to controll the draft on a chimney that tall

 

[mykullshepherd]

Is there anyway you can test your draft on the existing chimney, I'm thinking that if you go with an 6" oval liner you may create an excessive draft (3) stories of 36ft. You may need to go with a larger liner to slow things down some.

What is the best way to test the draft? Right now it works fine, although it is quite difficult to a fire started when it is cold - the smoke just rolls back out into the room until everything gets heated up. I'm having a local stove shop come out and run a camera down the chimney to check it all out.

 

[mykullshepherd]

Yes you need a stainless liner. But i would remove the clay liners and put in a 6" insulated liner. You will probably need a pipe damper to controll the draft on a chimney that tall

What is the benefit of the insulated liner over a non insulated one?

 

[bholler]

What is the benefit of the insulated liner over a non insulated one?

It drafts better has less buildup is safer and in most cases is required by code and ul listings

 

[kennyp2339]

What is the best way to test the draft? Right now it works fine, although it is quite difficult to a fire started when it is cold - the smoke just rolls back out into the room until everything gets heated up. I'm having a local stove shop come out and run a camera down the chimney to check it all out.

If those are the symptoms then you don't have an excessive draft issue, you will actually improve your draft (no smoke roll out) by installing an insulated liner down the existing masonry chimney.

 

[begreen]

The marginal draft could be due to a leaky cleanout door or just the basement location. Basements are common negative pressure zones.