WILL 6" PIPE WORK?

[danrclem]

Right now I have a Fisher Granpa Bear in my basement with an 8" outlet necked down to 6" pipe going to the thimble which is 6" going through the wall and a block chimney with a 6"X6" square liner. Everything works well and the stove draws well.

My problem is that the square block is getting a couple cracks in it that goes through several blocks. I'm wanting to change this and go with a good metal chimney. My question is since the most that can go through this system right now is what can go through the 6" round stove pipe will a 6" round chimney be enough or would it be worth the extra money and put 8" through the wall and up the chimney? If I used 8" I'd have to enlarge the opening through 9" of concrete wall which I'd do if it meant a better system.

What do you guys think?

Danny

 

[webby3650]

Ideally you could get a new EPA stove with a 6" outlet, knock out those tiles and replace them with an insulated 6" liner, or knock out those tiles and install an 8" insulated liner and 8" thimble. Sometimes an 8" stove with 6" pipe works for some reason, it's not cool but it works. If your flue tiles are cracked they really need to come out to make way for an insulated liner.

 

[danrclem]

I don't have any idea if the flue liners are cracked but they very well could be. I really would hate to get rid of that old Fisher stove because it heats so well and I already have it. Another reason that I wanted to tear the chimney down and use a metal insulated chimney pipe is so that I could build a structure around it to make it look better and I would be fearful of enclosing a block chimney even it did have a liner. I'm guessing that it is more likely that the 8" would work better than the 6" since the stove has an 8" outlet. Would that be an accurate statement?

 

[webby3650]

I didn't realize you wanted to remove the the masonry chimney, depending on the height, I think it would be cheaper to re-line. You cannot attach anything combustible to the chimney unless you put an insulated liner down down it, which means removing the tiles. Yes, your stove will perform better with an 8"pipe all the way up. Everybody loves there old stoves and I understand that, But a new stove would be at least 75% efficient and the Fisher is about 30-45% efficient, that is a lot less wood to buy or cut and split and move to the house!

 

[Fsappo]

Knock down the chimney, buy a new 6" class A pipe with a new stove that qualifies for the tax credit and sell your old stove for a few hundred bucks.

I wouldnt run your stove in a 6" chimney and if you compare the cost of an 8" chimney to the cost of a new stove with the 6" chimney and the sale of your old stove..considering the improvements the new stoves offer, you may find a new stove the best deal for you.

 

[Wet1]

If everything works well with the 6x6, I'm sure it would be fine with 6" round. Technically, it's frowned upon (necking down from 8" to 6"), but it will work fine.

 

[Fsappo]

Do you really feel comfortable advising someone to use a 8" smoke dragon on a 6" flue and stating it as a fact " but it will work fine."? I'd rather say it "should" work fine. I think we as forum member should be very careful when advising someone to do something that is potentially unsafe or not to code..we arent dealing with curtains here, we're dealing with fire.

I'll say it again for the OP...of all the options you hear, the ones that involve running your 8" stove on a 6" flue should be at the bottom of the list

 

[Wet1]

Frank,

I'm not advising him to do anything. I told him it's technically frowned upon (which it is), but it will work (which it will since he's been running it all along on a 6"round/6"x6" flue). He's a big boy, he can do what he wants with that info. So no, I wont lose any sleep tonight from posting what I did.

 

[danrclem]

Thanks for all of the replies. I think it's unanimous that an 8" outlet stove should be ran with an 8" chimney. I don't have the funds right now to do a stove and a chimney and since I definitely need a chimney I'll have to do it first. Webby 3650, how do you get the liner out of a chimney without tearing it down? I have one more question. If I buy a stove later on that has a 6" outlet will it work well with an 8" chimney?

 

[Fsappo]

Chimney Sweeps have a tool that removes tiles from the inside by smashing them to bits. A 6" stove "should" work fine on an 8" chimney

Thanks for all of the replies. I think it's unanimous that an 8" outlet stove should be ran with an 8" chimney. I don't have the funds right now to do a stove and a chimney and since I definitely need a chimney I'll have to do it first. Webby 3650, how do you get the liner out of a chimney without tearing it down? I have one more question. If I buy a stove later on that has a 6" outlet will it work well with an 8" chimney?