After 6 years with my Hearthstone Mansfield (big firebox) I finally decided to improve my draft by correcting what I was told by knowlegeable professionals was an oversized, cold chimney. Our original setup was the 6" stove pipe going to a 90 degree into an 8" thimble that emptied into a 8 X 12 flue tile in an exterior masonry chimney (stuccoed cinder block). After debating over a draft inducer fan or relining we settled on the liner. We installed 6" 316 SS foreverflex kit with insulation wrap and ran 6" through the thimble such that the entire run of 24 feet from firebox to cap is 6". The inner diameter of my flue was 7.5" but the liner would not go down, so we had to flatten the pipe a bit to accomodate the wrap and some offset tiles. The installtion looks beautiful and makes sense on paper but my draft is now WORSE than before. Smoke comes in the house when the door is opened even when the fire is established. We are miserable and at a loss. Any suggestions appreciated. Thanks.
Poor draft after relining
- Thread starter joe308
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jtp10181
Minister of Fire
What kind of connector pipe do you have inside the room? Single wall?
They should not have crushed the liner too much since you had 7.5" inside. But if it was crushed down too much it could cause trouble.
We have ovalized some and not had any call backs. We have also installed a few rigid oval liners this year and they seem to be working great.
I assume you now have a cap, and before you may or may not have? Make sure the cap is not too restrictive.
They should not have crushed the liner too much since you had 7.5" inside. But if it was crushed down too much it could cause trouble.
We have ovalized some and not had any call backs. We have also installed a few rigid oval liners this year and they seem to be working great.
I assume you now have a cap, and before you may or may not have? Make sure the cap is not too restrictive.
Corie
Minister of Fire
Forget that smoke comes in the house when the stove is in operation (are you opening the door slowly?) for a minute. What's operation like otherwise? Is the stove responsive to small or larger changes in the air control setting? Is the fire crisp and active with the air control open?
The cap does not look too restrictive to me, but I could be wrong. It's pretty tall with a wind baffle around it almost like an extension of the stack, so there are openings above and below. The draft seems to develope over time, but is reduced compared to the pre-liner behavior of this stove. We get a decent rolling file, but due to the reduced flow must run this with the air control fully open at all times. I'm wondering if it got kinked a bit during the install. I compressed this pipe myself which although ribbed was pretty easy to flatten, so I'm wondering if we could run a cone up (or down) to push out any problems?
As for the other questions, yes I'm opening the door slowly and the stove pipe is double wall. Everthing is the same as before the liner, except for changing the thimble pipe from 8" to 6" and conneting to the 6" liner to the top. Thanks.
iceman
Minister of Fire
i think you should have put a tee on the liner and used single wall from the tee/ thimble to your stove
i may be wrong but i think your kink in the liner is where you pulled into your house ...a flexible liner is ment to flex not bend and so forth
although it can the rigid shouldn't be bent excessively
i may be wrong but i think your kink in the liner is where you pulled into your house ...a flexible liner is ment to flex not bend and so forth
although it can the rigid shouldn't be bent excessively
webbie
Seasoned Moderator
Well, the barn door is already closed, but I might have have told you that an 8 x12 chimney was not far oversize for such a big stove. Consider that the interiors are usually 7x11 or smaller....and that stove is pushing a 6" flue as far as possible - in other words, that stove should probably have been built with a 7" or 8".
I also suspect that the pipe may be kinked or flattened too much....possible.
You can get both rectangular flex pipe or professionally ovaled round flex. In either case, insulating it probably made things harder - in tight chimneys the insulation should be left out or poured in afterwards.
Another point - flex is rough on the inside and therefore a 6" flex does not draft like a 6" rigid. Rigid pipe might have worked better.
I'm not suggesting this stuff for you to replace it - just for the record if other people research this thread!
As far as your particular situation....is there a TEE at the bottom? Describe how the wall connection is. If you can use 2 45's from the stove to the wall instead of a 90, the flow might be better. Make sure all interior pipe joints are cemented with furnace cement.
You can add some draft by extending a couple feet of rigid liner out the top - if this works, you might be able to encase it with an Extendaflue.
I also suspect that the pipe may be kinked or flattened too much....possible.
You can get both rectangular flex pipe or professionally ovaled round flex. In either case, insulating it probably made things harder - in tight chimneys the insulation should be left out or poured in afterwards.
Another point - flex is rough on the inside and therefore a 6" flex does not draft like a 6" rigid. Rigid pipe might have worked better.
I'm not suggesting this stuff for you to replace it - just for the record if other people research this thread!
As far as your particular situation....is there a TEE at the bottom? Describe how the wall connection is. If you can use 2 45's from the stove to the wall instead of a 90, the flow might be better. Make sure all interior pipe joints are cemented with furnace cement.
You can add some draft by extending a couple feet of rigid liner out the top - if this works, you might be able to encase it with an Extendaflue.
My set up is the same lenght liner 316 ti but mine is 5.5" as I could not get a 6" down my clay chimney. I had to push/pull the liner past two turns to make it into where my thimble is on the wall in the basement.
My set up is not insulated and on an outside wall chimney. My draft is so strong I installed a dampner just above the stove.
Me thinks some where your liner is pancaked flat. My liner is 24' long as well with an additional 4' of single wall pipe in the house.
I think you are going to have to determine if the liner is restricted.
If it works for now once the weather warms up I would think you might be best to pull the liner back out and do a visual check unless you have access to a camera you can put down it to check for a restriction.
My set up is not insulated and on an outside wall chimney. My draft is so strong I installed a dampner just above the stove.
Me thinks some where your liner is pancaked flat. My liner is 24' long as well with an additional 4' of single wall pipe in the house.
I think you are going to have to determine if the liner is restricted.
If it works for now once the weather warms up I would think you might be best to pull the liner back out and do a visual check unless you have access to a camera you can put down it to check for a restriction.
This was a complete kit with a matching cap and 6" tee installed at the bottom of the run just outside the thimble we just ran rigid 6" stove pipe through the thimble to the existing stove pipe that make the 90 degree. I was going to use the 5.5 flex pipe, but Hearthstone told me the 6" was a must and not to go below the stove collar size. The flue should have been large enough to accomodate this liner, but there were a few tight spots and it may be flattened a little too much somewhere along the line. I did not use cement on the inside pipe fittings, but never have in the past. What do you think about running a 4" or 5" pulling cone down the interior of the pipe to open it up some? Thanks for all the suggestions.
iceman
Minister of Fire
gpcollen1
Minister of Fire
Good idea with the cone, if you have one. If not, use some 4" PVC with a cap and then something bigger. I would think you could Cowboy Engineer something that will work, I just think if you do have a flattened liner, you may want to go gradually larger in size.
Pull a brush through it first. Easier to get a stuck brush with ropes on both ends back out than a stuck cone/piece of pvc/keg of nails or whatever.
webbie
Seasoned Moderator
Every little thing helps and hurts. Use furnace cement between all the joints that you can get to! Think of it this way, if you have a vacuum cleaner and the hose had holes in it, would it suck as well at the end? Answer - no.
Tighten up the ship.
It might even help to cut the horizontal pipe near the wall and install a 45 and then head toward the stove and install another 45 - better flow.
Tighten up the ship.
It might even help to cut the horizontal pipe near the wall and install a 45 and then head toward the stove and install another 45 - better flow.
Thanks for the tips. I'm thinking a 4" cone that is about 4 7/8 outer diameter with rope going both ways so we pull back if need be. It may be a few weeks before I can get help to do this and by then we may be out of burning season. Either way, I'll post the verdict once we get it done.
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