Help with changing from 8" to 6" chimney

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n6crv

Feeling the Heat
Aug 5, 2007
332
Hillsdale Co. Michigan
Hello, We have been using a old US Stove co. Forester we installed in the 80's. It had a 8" flue going into a triple wall chimney. At the time the triple way was the great thing. Well we use it for about 2 years and just started using it again 4 yrs ago. The creosote build up was very heavy I was cleaning the chimney every 2 weeks never could get the chimney hot enough to keep the creosote down. So last year I thought I would try to "fix" the problem, I packed the the inter wall of the chimney with Rock Wool. It did help keep the flue warm and still the outside was cool. We are going to change the stove this year to a new EPA Certified one. It has a 6" flue. What I need help with is if my way will work and be safe. I removed the Rock Wool so now it's back to a air cooled chimney. I want to run a 6" pipe up inside the 8" and keep it centered with using 3 screws sticking out of the 6" about every 2 feet. Then going to fill the void around the pipe with Vermiculite as it is fire proof and a good insulation. It would still be keeping cool as the 2 outer layers will still move air. Is there anything wrong with going this way? I was thinking of using 24ga steel pipe for the liner but if needed would go for stainless. Thanks for the help!
Don
 
Hi there. I had a similar situation where my existing class a chimney was 8 inch but my new stove really likes a 6 inch pipe. I think most people here will tell you to just install a new 6 inch chimney. What you described will definitely work (I had similar thoughts, but when you price the rigid stainless steel liner pipe versus just getting all new 6 inch pipe, you're not saving a heck of a lot. Good luck!!!
 
Hello MrKenmore, I would go with a 6"chimney but the cost is almost $100.00 a foot. I have found Stainless 6" 24 ga in 2ft pieces for $10.00 a piece so for 40.00 I can reline the old chimney as it in only 8ft. One more reason I would like to try the reline if safe is because we just had a new roof put on the house and I sure don't want to have to change anything. Thanks for the reply.
Don
 
This is not a situation that is directly addressed in any lit that I know of, but my comments:

Your original modification of the chimney (rock wool) was a dangerous move - this type of chimney is engineered very carefully and should not be modified....I'm glad you changed it back to original factory config.

The reline which you mention should be safe as long as the air cool functions of the original chimney are left intact.

Note: new insulated 6" chimney can be found for about $30 a foot (discounted) for the DIYer - maybe even less at a Lowes, etc.- You will spend about $500 total for the chimney parts including support. That is not a lot considering it will last 20-25 years (that's $20 a year)....
 
Thanks, I will check with some on the Lowes around here. Yes the chimney is now back to stock. Another question without starting a new post has anyone used the Englander 13-ncp? Was going to go with that one or looking at a Vogelzang Defender. Thanks for the help.
Don
 
From what I've read stay away from the Vozelgang, We have a couple of Englander employees here on the forum I'm sure they may pipe in soon.
 
How large a space are you trying to heat with the stove? Will this be running 24/7 or evenings and weekends?

If you're content with the stove size, go with the Englander, you'll get good support for the stove in spite of the great price. Hard to beat for the value.
 
Don't line it with regular stove pipe that stuff will be swiss cheese in a couple years. Go stainless if you must do the reline route but outright replacing the chimney will be your best bet. Also what brand and model is the chimney? It is possible that you have 1700 degree chimney not 2100 degree chimney like you'll need for the new stove install to pass muster.
 
Hello, trying to heat around 1200 sq ft max. Our old Forester would just cook us out of the den. To get it to were the flue was around 300 deg the room was 95. There was really no way to run it on low. I tried small fires but the flue would stay below 200deg. That is one reason I want to go with the new stove. I like the looks and size of the 13-ncp but would like it even better if it had legs. The stove will be used most of the day and the furnace at night. We are in Southern Michigan so at times it does get cold. With the old stove the furnace would stay off all day. The chimney is about 22 years old. When I cleaned it a couple of days ago was surprised on how good it looked. The stainless pipe cleaned up great. I'm not sure what the temp rating on it is. I know it has a UL sticker on it and saids to keep 2" away form things that burn. For some reason HT103 or something like that rings a bell. Thanks for all the fast replys.
Don
 
The bad creosote problem may be more related to the earlier stove than to the chimney. A straight up chimney with part of it being though the attic usually drafts pretty well. If you have inspected and cleaned the chimney...and all looks good, it is possible that the new stove will work fine with the 8" chimney. If you do this, put a 8 to 6 adapter at the ceiling and then run the 6" down to the stove.

You can try this for a couple weeks in the fall, and then still have plenty of time to replace or line the chimney if it is not satisfactory.
 
Am I the only one here that thinks that chimney only being eight feet high is going to be a problem? And sticking screws through the liner pipe to center it?
 
Guess I should of done a better job on telling about my screws. Thinking about using 1/4" stove bolts with 2 nuts. The rounded head would be on the outside to center the pipe. I don't want to take any chance of the bolts poking a hole into the chimney. Also it does not need to be a real tight fit so that the heating of the pipe should not cause any outward force on the chimney. Also the Vermiculite would also give the 6" alot of support in keeping the pipe centered. I have decided that I will go with stainless. There is 6' of chimney above the roof as were it goes thru the attic it is only about 2ft. When I first put the chimney in I thought 8' was a little short so did try adding a 4' on the top but made no difference in the draft. The 6' looks better above the roof anyway.
Don
 
N6CRV said:
Hello, trying to heat around 1200 sq ft max. Our old Forester would just cook us out of the den. To get it to were the flue was around 300 deg the room was 95. There was really no way to run it on low. I tried small fires but the flue would stay below 200deg. That is one reason I want to go with the new stove. I like the looks and size of the 13-ncp but would like it even better if it had legs. The stove will be used most of the day and the furnace at night. We are in Southern Michigan so at times it does get cold. With the old stove the furnace would stay off all day. The chimney is about 22 years old. When I cleaned it a couple of days ago was surprised on how good it looked. The stainless pipe cleaned up great. I'm not sure what the temp rating on it is. I know it has a UL sticker on it and saids to keep 2" away form things that burn. For some reason HT103 or something like that rings a bell. Thanks for all the fast replys.
Don

interesting you should mention the legs, we are shippiing all 13 series , 12 series and 30 series on pedistals this season , but when you uncrate the unit you should find a set of legs inside, the stove can easily be refitted from leg to pedistal and back if desired, the flue height will be the same in the 13 series (in case you are measuring for that new flue ) IMHO i would look at a new flue, should you want any more information on the englander units please feel free to ask , thats why im here.

mike ESW
 
Hello Mike, now that is service! I get on the 1911 forum and the factory rep in on there. Never expected to get a rep on here also. Thanks for the help from all. Great on getting the legs with the stove as my wife likes the looks of the stove with legs.
Don
 
hey no prob, i enjoy it in here, quick hint though on the leg thing , make sure you get a unit that was built in 2007 , left over 2006 stoves do not have the legs included, we just started that this year. so check the build date on the unit
 
That could be interesting as I was going to order it from our local Hardware store. They are a "Do It Best" store and show that they can get it. I live in a real small city so like to get local if I can and the cost is close to the big box stores. But how would we be able to tell when it was made before it gets there? Wonder if they can ask the supply house?
Don
 
give me a couple days to check , i'll see if DB warehouse sold through last season and what they have ordered from us this season , i cant do that from home so i will have to get someone to check that for me monday , i'll let ya know what i find out
 
Wow! Mike from ESW, no offense but I thought Napoleon has a tremendous saturation of product. You guys even have them beat. why would you set up dealers all over and so close ?
 
actually , it works well for us. we sell mostly in the DIY market and in that market the more chains that carry your product the better you end up. we currently carry product in lowes, home depot, ace true value, sutherland lumber , do it best , ziegler lumber out in the northwest, tractor supply and several others. with smaller franchises such as DB they are able to buy through warehouse which allows them to keep pricing very close to the bigger fish like depot/lowes.

by the way . i looked at your site as well, beautiful product line. also, im remiss in saying welcome aboard, great to have another industry rep here at the hearth. look forward to working with you
 
Thank You Mike.
Yes, I carry a very unique product, High end contemporary and traditional . I also carry regular good workhorse stoves like Buck Stove and Blaze King.
Certainly nothing found at Home Depot :) :cheese: :roll: (Only Kidding !)
Rob
 
As they say in the car biz, there is an arse for every seat! It's always hard for New England dealers to understand that in much of the south and elsewhere stoves were often sold by the local furniture store or other trading post...and now by the big boxes and hardware chains. It is actually a good thing in my opinion, because it means wood stoves have gone relatively mainstream.....
 
i actually hesitated... but i'll say it anyway. (no i aint advertising lol) the boss has always said we build for the working man, we have a product line that can put a quality stove in virtually any home regardless of income. and its true, and we're proud of it.
 
Fiamma said:
Thank You Mike.
Yes, I carry a very unique product, High end contemporary and traditional . I also carry regular good workhorse stoves like Buck Stove and Blaze King.
Certainly nothing found at Home Depot :) :cheese: :roll: (Only Kidding !)
Rob

hey , buck & BK are both great lines, we actually have a blaze king rep on the forum now , his name's mike ( we're everywhere lol) i didnt look that far to see what you were carrying in the "workhorse" variety but the high end stuff you have was starting to make me drool.
 
Actually, We have two sites the traditional stuff is on www.hsfireplace.com and the high end contemp is on fiamma.us,
We are also the Importer of Nestor Martin stoves from belgium, we share US territory with evolutuin trade group out of Chicago, they are the Importers of Max Blank wood stoves from Bavaria.
 
I would NOT do the bolts in the pipe reline trick - it seems overly difficult, and less than fully desirable. If I understand what Elk has said in the past, it might also not be code compliant - my understanding is that you aren't supposed to have joints in the liner where they can't be seen?

At any rate, rather than doing the bolt thing, I would get a rock wool insulating blanket like is used on corrugated liner and just wrap that around the liner as I slid it down the existing pipe - that will give both insulation and centering in one step.

The biggest problem I see with doing the bolts is that you are going to have the nuts and surplus bolt threads sticking into the smoke path, representing a slight but measurable flow restriction / turbulence, and acting as condensation points for creosote deposits to start, while making it that much harder to clean the pipe. This is not good - you want the smoke path to be as smooth and clean as possible.

Gooserider
 
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