chimney sizing q's when shopping for new stove

[OhioBurner©]

Still havent tried the new insert out yet but the old wood monster really needs to go too... Havent decided for sure on what to replace it with but had some questions about the effect of the chimney. I know we had to put 6" up the existing masonry chimney for the insert since the existing fireplace flue was too large. But I wonder the same about the freestanding stove... our current stove is necked down from 8 to 6, goes up, 90*, goes back to the wall and up to 8" again and passes through the wall with maybe a foot or so 8" clay liner than its a masonry chimney up through the attic and about 3' above the house. Due to the upstairs (attic) being barely tall enough to stand in the middle, this isnt a very long run of chimney, I'd have to measure but I'd say maybe around 15'? Also its rectangular, I forget exactly, around 8 I believe.

Is 8"x12" going to be too large for a modern medium or med/lrg sized stove (thinking like the Jotul Castine or Oslo)? I dont really see how I could possibly re-line this chimney with it being in the wall and a 90* inside it...

I also dont have money now to reline the whole thing... was really hoping I could get a stove that just needs set in place and the stovepipe slipped on...

Maybe I can take some pictures tomorrow might make it easier to see (at work now).

 

[begreen]

Pictures will definitely help, but I can almost guarantee that the Castine would be very unhappy with that setup.

 

[OhioBurner©]

OK I just got home from work and grabbed the camera. I figure pics will shed some light on the situation. Unfortunately it wasnt very light yet and our interior lighting is dim, and the flash is broke on the camera. So you'll have to forgive the grainy high ISO / low shutter speed pics.

Old stove (is this what you all refer to as a smoke dragon?):

Whatever you call this piece that goes from the room through the wall into the masonry chimney (8" diameter), and sorry I havent cleaned it yet:

And the chimney as viewed from outside (I didnt climb up there this morning but sure its 8x12 or very close to that):

So whats the verdict? Am I screwed? Options?

 

[vvvv]

whats with the piece of copper pipe?

 

[oldspark]

I always like to tell people to try it before spending a lot of money, it might work fine even though it isnt in spec., different brands of stoves react differently to size of chimneys so yuo may luck out.

 

[begreen]

whats with the piece of copper pipe?

I think that is a flashlight.

pile 'o wood, the pictures help a lot. It's a lot simpler setup than the description. I would go ahead and line the flue with a 6" liner for a more trouble free installation. It is a bummer to find the stove operating poorly when there is snow on the roof. The reason being that this is a short flue to start with. There will be at least two 90° turns in the smoke path to an only 15' flue which effectively is going to make it function more like a 5' flue. The additional cross-sectional area of the flue is going to further reduce draft. It is about 2.5 times the required area. The Castine is a shallow firebox. It really likes a decent draft or there will be smoke spillage when the door is opened. The Oslo is better, but still I think it will want the liner.

You might be able to struggle with an elbow on the end of the liner down the 8x12 flue, but instead I would use a tee with a leg down to the cleanout door on the chimney with a cap on the bottom of the leg. The tee comes with the snout off, it is attached once in position. Here are instructions http://www.chimneylinerinc.com/chimney_liner_installation.htm or this video should be helpful: http://www.chimneylinerinc.com/rcsrcs.swf (requires flash player installed in the browser.)

 

[oldspark]

Not disagreeing with you BG but there are old posts on here where some people spent a fortune trying to fix a draft problem to no avail and bought a different brand of stove and the problem went away, I did not mention the time frame thing in my post but yes dealing with it after its cold would be PITA but I think more money is spent in some cases than needed and he said he did not have the money to reline the whole thing. If the thing works the thing works no matter how the numbers come out, this is not rocket science.

 

[begreen]

If this was a two story setup, I would also be inclined to try it as. Suppose there is no harm done as long as it's before the snow gets on the roof. Working on a wet metal roof is no fun.

 

[vvvv]

antenna mounted on chimney aint a good idea, so i've read

 

[OhioBurner©]

I always like to tell people to try it before spending a lot of money, it might work fine even though it isnt in spec., different brands of stoves react differently to size of chimneys so yuo may luck out.

Yes, and I hope there is enough experience here to find folks that have tried a similar setup since I dont really have money to just buy and try if you know what I mean.

whats with the piece of copper pipe?

If your talking about the black thing yes its a mini mag flashlight since the lighting was very dim (has the front removed so it might not look like a maglight at first glance).

pile 'o wood, the pictures help a lot. It's a lot simpler setup than the description. I would go ahead and line the flue with a 6" liner for a more trouble free installation. It is a bummer to find the stove operating poorly when there is snow on the roof. The reason being that this is a short flue to start with. There will be at least two 90° turns in the smoke path to an only 15' flue which effectively is going to make it function more like a 5' flue. The additional cross-sectional area of the flue is going to further reduce draft. It is about 2.5 times the required area. The Castine is a shallow firebox. It really likes a decent draft or there will be smoke spillage when the door is opened. The Oslo is better, but still I think it will want the liner.

You might be able to struggle with an elbow on the end of the liner down the 8x12 flue, but instead I would use a tee with a leg down to the cleanout door on the chimney with a cap on the bottom of the leg. The tee comes with the snout off, it is attached once in position. Here are instructions http://www.chimneylinerinc.com/chimney_liner_installation.htm or this video should be helpful: http://www.chimneylinerinc.com/rcsrcs.swf (requires flash player installed in the browser.)

Thanks for the info. The Castine was just one idea, heck I even contemplated the Firelight since the door is on the right side and if I wanted a whole house heater the firelight would actually be the right size (close to 3,000 sqft) but I have the other insert if I chose to run it 24/7 that greatly reduces the heating demands on the freestanding - but that doesnt help my large chimney problem. Maybe I dont have much a problem now because we have used this one as a whole house heater and usually have it cranked. It is huge, if you couldnt tell from the pics. It just eats 3-4 large splits every few hours.

Begreen - I looked at that link but I am not getting it. And the video wont work for me (at work pc). I didnt realize you could even put a new liner in such a setup? Is there really room? I guess the parts I dont get is how you would attach the T part that goes through the brick wall into the chimney. I dont see how an elbow would possibly fit unless were talking like 4" pipe and I dont see how a T would unless it was super low profile and the pipe going through the wall was just pressed in? And if that would work how do you terminate the bottom? The chimney goes down into cellar and there is a small cleanout door. You wouldnt have access to any cap and you wouldnt want to just leave the bottom of the pipe open would you? Or would that be ok?

Sorry for all the newb like questions, I grew up pretty much my whole life burning wood but really no nothing about chimney design! My folks went through an exterior wall and was triple wall stainless and easy to deal with. A masonry chimney on an internal wall I really have no experience with (just moved into this house a couple years ago).

I have no problem spending money to do it right if there is a good solution, will just require another year to get the $$$. We just dropped $1000 on propane that will hopefully get us through the winter for backup and the days were not home... Thanks for all the info!

 

[branchburner]

What about trying a newer EPA stove that has an 8" flue collar?

 

[BrotherBart]

My two eight by twelve clay flues drafted like crap until I lined them. And one is 21' and the other over thirty. Line the sucker.

And yes, one was just like that one coming off the stove into a eight inch crock via a reducer.

 

[OhioBurner©]

What about trying a newer EPA stove that has an 8" flue collar?

Well to be honest out of all the times we've been in looking for stoves I havent come across one, although I didnt ask em if they had any, just looking at the models that I liked. But I assume your only going to find an 8" flue colllar on a larger stove, which I am thinking I dont need.

My two eight by twelve clay flues drafted like crap until I lined them. And one is 21' and the other over thirty. Line the sucker.

And yes, one was just like that one coming off the stove into a eight inch crock via a reducer.

What size/stlye liner did you use? Did you use a T? If so how do you terminate the bottom?

 

[laynes69]

I agree with lining the chimney. We had a 7x11 flue that was 32' tall. Things seemed to draft okay until we could close the damper and once the temps in the flue dropped, we had horrible draft. I never had a problem with the old furnace, but too much heat was put up the flue. I now have a liner and the first couple fires this year, I have seen the flue drawing 3x's better in 50 degree weather. No matter the temps outside, I have draft. I think older stoves dont see this because of higher flue temps which will carry a better draft. When a newer more efficient unit is put on the same chimney, you can see low draft, condensation, and performance issues due to less heat going into the chimney.

 

[branchburner]

What about trying a newer EPA stove that has an 8" flue collar?

Well to be honest out of all the times we've been in looking for stoves I havent come across one, although I didnt ask em if they had any, just looking at the models that I liked. But I assume your only going to find an 8" flue colllar on a larger stove, which I am thinking I dont need.

If you want cast iron, then no, but if you like steel, how about a Buck 80? Firebox is only 2.6, which sort of makes me wonder why it's 8" for the flue. But the cross-sectional area for 8" pipe is about 50"sq (vs 30"sq for 6" pipe), and if your flue is 8"x12", then you're talking a 2x versus a 3x difference. Might work.

 

[BrotherBart]

What size/stlye liner did you use? Did you use a T? If so how do you terminate the bottom?

I went with 5.5" liners in both flues. I at first tried a double wall six inch in the 21' flue but didn't like the fact that I have to ovalize the the thing which caused it to delaminate inside. So I put a 5.5" liner in it and one just like it in the one for the crock in the basement. It was such a pain in the butt trying to get that tee down the basement flue I finally just took it off and pulled the liner through the crock. The clean-out was going to be too high up to reach through the small clean-out door anyway. I just use a rope and pull the brush right into the trash bag at the thimble.

 

[begreen]

Maybe this version of the video will be easier to see.

 

[BrotherBart]

I would really like to see a video of Brian at Rockford actually doing that with an actually tee snout and crock. :lol:

 

[oldspark]

My two eight by twelve clay flues drafted like crap until I lined them. And one is 21' and the other over thirty. Line the sucker.

And yes, one was just like that one coming off the stove into a eight inch crock via a reducer.

Well theres your answer, probably going to have to reline your chimney.

 

[OhioBurner©]

I think I'll have to try and watch the vids at home tomorrow - just can't see em at work. All I get is red X. Alot of stuff is blocked here, youtube, etc. As long as it is possible to reline that sounds like what I'll have to do. Juts sucks I moved into a house in part because it was already setup with a stove and fireplace, only to learn how crappy they were and putting in new stoves and I cant even use the existing chimeny! Oh well... I'm going to do it right so thanks for all the info guys... I am going to take my time with the freestanding replacement and do my research and shop around. This site has probably saved me from a huge headache had I tried to just slap a stove in there.

Cast iron = yes. Looks wise the Jotul Castine through firelight models are my ideal look, or VC - grew up with a Vigilant that my folks had for 25 years.

BTW anyone have any clue what kind of stove that is?

 

[firefighterjake]

I think I'll have to try and watch the vids at home tomorrow - just can't see em at work. All I get is red X. Alot of stuff is blocked here, youtube, etc. As long as it is possible to reline that sounds like what I'll have to do. Juts sucks I moved into a house in part because it was already setup with a stove and fireplace, only to learn how crappy they were and putting in new stoves and I cant even use the existing chimeny! Oh well... I'm going to do it right so thanks for all the info guys... I am going to take my time with the freestanding replacement and do my research and shop around. This site has probably saved me from a huge headache had I tried to just slap a stove in there.

Cast iron = yes. Looks wise the Jotul Castine through firelight models are my ideal look, or VC - grew up with a Vigilant that my folks had for 25 years.

BTW anyone have any clue what kind of stove that is?

The one in your pic . . . I'm thinking it is either a) a boat anchor or b) future scrap . . . but that's just a biased guess on my part.

Thumbs up on the Jotul line up . . . however personally I would pass on any of the VCs . . . at least for now . . . too many questions have not been answered with them still in terms of warrantys, parts and reliability since the new company took over VC.

My own take on the liner . . . go for it . . . I suspect you will be happier in the long run . . . plus I thought it qualified under the tax credit deal . . . I could be wrong with that part . . . but in either case I would rather make sure the whole set up works and works well rather than get a nice stove and find it doesn't work very well just because of the draft.

 

[OhioBurner©]

FFJ - Yeah I have no problem going with a liner - I just couldnt see how I could possible do it, with the 90* turn basically being out of reach inside the chimney through the wall. I just cant picture how you could hook something up were you cant reach if you know what I mean. Yeah I am not even considering VC after reading here - just saying thats the 'look' I like (growing up with a vigilant). Dont care for the modern look or the steel ones (neither does the wife).

Yeah it qualifies for the tax credit but I already chewed up most of that with the Jotul Rockland install. Got $500 left I can get 30% off thats not very much. When I replace the scrap iron I plan on moving it into the pole barn, it still throws heat, and I wont be worried about how much wood it eats up when I would only fire it up 2-3 times a winter if I was doing some all day or weekend long project in the barn.