Another SS chimney liner question from someone new to this

[woodchopper]

Hello, I did a search of back post and didn't get all the info I needed. I'm buying a liner on-line for my woodstove in a fireplace application. I haven't measured the passageway where the fireplace damper is now sitting yet. Once I measure it I'm hoping but pretty sure a 8" will fit. From what I measured so far it looks like a 15 foot section plus the tee will put the liner in the proper place to hook up to the stove with a few extra inches to spare. I/m pretty sure I'll have enough draft but after reading some of the back post I'm worried that it might not be. What do you think ? I'm very excited about being able to replace the current fireplace with a woodstove. I can't wait to get it up and running. BTW, I LOVE this forum and burning wood in general

 

[edthedawg]

What stove are you installing? 6" seems to be a bit more common - you putting an Equinox in or something?

Is the fireplace on an exterior wall of the house? or more central to the house? If it's external and you go w/ an insulated 6" liner, then having the 8" dia opening capacity will serve you well...

If you are concerned about the length and can't measure accurately, just get a longer liner and cut it back, but it seems you're more worried about drafting - your answers to the first two questions likely help direct that discussion...

I'd ask if you have sufficient wood stored up and ready to go, but from your handle, I'm gonna reckon you're covered there...

 

[weezer4117]

do you have a manual for the stove? im a little concerned with the length of the chimney not being long enough. most of your stoves, like mentioned in the previous reply, are 6" and require a chimney longer than 15'.

 

[woodchopper]

I'm putting a older model Warner in for a stove. My BIL gave it to us. We're going to measure the passageway at the damper and see if I have to ovalize the last 3' or so to make it fit through there.
Don't have a manual but I can probably find one on-line someplace. My chimney probably IS too short but I'm going to give it the old college try anyway. Anything will be better than what I had with the fireplace.
The fireplace is on a exterior wall and by the sounds of things I was wrong thinking a larger sized liner would make the stove breathe easier. The stove shops and online places I've talked with said to go with a 8" liner because the stove was set up for 8".
My wife and I do have alot of wood here and yes I LOVE to cut, split, and stack wood. We've taken quite a few trees down here in MA. because of a new septic system and at our house in Maine I buy my wood in tree length. I cut it up there two years ahead because I have a soapstone woodstove that won't run on anything except very dry wood. It's a good practice to use anyway. Like I said before I can't wait to fire this stove up.

 

[weezer4117]

yea do some research on your stove to see what the recomended chimney length should be. was the stove "set up" for an 8" exhaust or is that the factory diameter? generally you want to keep the liner the same size as the flu on the stove. although i have seen people reduce the diameter to meet their needs. the manufacturer will not suggest doing so

 

[woodchopper]

yea do some research on your stove to see what the recomended chimney length should be. was the stove "set up" for an 8" exhaust or is that the factory diameter? generally you want to keep the liner the same size as the flu on the stove. although i have seen people reduce the diameter to meet their needs. the manufacturer will not suggest doing so

Factory diameter. So maybe I should stick with 8" ?? I'll ask the liner company when I order it within the next day or so. I'll google it tomorrow and see if I can find a on-line manual.

 

[weezer4117]

i would wait to see what the maunual says before ordering, im sure thats what the liner company will say. if the stove has a 8" flu then the manual will probably only suggest an 8" chimney!! reducing to a 6" wont hurt anything. as a matter of fact it may help your draft, we will never know until you try!! i would definatley make sure that you insulate the ss (helps maintain constant high flu temps and cuts down on creasote buildup) just a rule of thumb that i go by, you can usually get away with taking an inch or 2 from a chimney diameter but never add to it!! (this applies to freestanders)

 

[woodchopper]

i would wait to see what the maunual says before ordering, im sure thats what the liner company will say. if the stove has a 8" flu then the manual will probably only suggest an 8" chimney!! reducing to a 6" wont hurt anything. as a matter of fact it may help your draft, we will never know until you try!! i would definatley make sure that you insulate the ss (helps maintain constant high flu temps and cuts down on creasote buildup) just a rule of thumb that i go by, you can usually get away with taking an inch or 2 from a chimney diameter but never add to it!! (this applies to freestanders)

Well as far as the 6" vs 8" I don't know WHAT I should do now. Almost everybody I've talked with has said to stay with 8" because that's what the stove is. I can insulate about 11-12 feet out of the 15' total but if I insulate the whole thing I'll never get it by the damper area if I use 8". The insulation kits I've seen require you to buy the whole 20' or 25' section. They are pretty pricey too. Once I have the stove going warm air will go up around the stove pipe up to the cap and keep it warm.....right? Won't that help with my draft ? I don't mind creosote build-up because my chimney is only 15' and it'll be super easy to clean. I COULD insulate pretty much the whole liner if I went with a 6" though. I'm going to look for a Warner manual online and see what it says to use. Thanks to everybody who took the time to help out someone new to fireplace to woodstove conversion.

 

[edthedawg]

The problem with trying to put the 8" insulated liner into the existing flue is just at the existing smoke shelf / damper area? Just cut that back, or remove the insulation right at the end. You need the insulation up top - not really so crucial right down by the firebox. Put a good blockoff plate in around the bottom and pack around the liner (on top of the blockoff plate, before its installation) with mineral wool insulation. You'll have everything you need.

I'd agree - if the stove is a factory 8" model, then keep it 8". Even w/ your reduced height. Full liner will help.

Getting this permitted / inspected?

 

[weezer4117]

the goal is to keep the chimney at a high, consistant temparature. the best way to do this is to have an insulated liner. so the 6" would be best for you. (by the way, i have a brand new 20' liner kit i need to get rid of!! pm if interested) again i am interested in knowing what the manual says about this. ill do some looking for the stove on the net, ill let you know what i find

 

[Wet1]

8" is certainly the correct technical answer, but I have a had time believing that you'd have a problem with 6", unless that stove is huge. In fact, I suspect you'd get better performance (since you have a short chimney) with the fully insulated 6" flue than you would with a partly insulated 8". The insulated 6" flue would likely provide better draft IMO... but an insurance company or building inspector might not like it.

 

[woodchopper]

The problem with trying to put the 8" insulated liner into the existing flue is just at the existing smoke shelf / damper area? Just cut that back, or remove the insulation right at the end. You need the insulation up top - not really so crucial right down by the firebox. Put a good blockoff plate in around the bottom and pack around the liner (on top of the blockoff plate, before its installation) with mineral wool insulation. You'll have everything you need.

I'd agree - if the stove is a factory 8" model, then keep it 8". Even w/ your reduced height. Full liner will help.

Getting this permitted / inspected?

Yes we called the town and they told us we didn't need a permit because we weren't actually changing the chimney itself. Our insurance company wants it inspected though. Don't want to mess with them.
The flue is 11 1/2 ID so a 8" liner will have plenty of room. Yes, it's just by the damper where it'll be tight and that's where I intend to ovalize it so it'll fit. I measured the gap this morning and if the whole metal damper comes out I've got a 7" gap there. I'll ask the liner place how much it'll cost for 13' of insulation but I doubt they'll be willing to sell that little. Anyone here know where I could buy a piece that long without buying a whole kit ?

 

[woodchopper]

Bet I could use this: (broken link removed)

 

[woodchopper]

. The insulated 6" flue would likely provide better draft IMO... but an insurance company or building inspector might not like it.

This is a strong consideration. Don't want to have to rip it out when it's a week old a redo it.

 

[woodchopper]

Just checked out the liner insulation kits at the place I'm going to buy from. $340 for a 25' kit. To say that is expensive would be an understatement. That would almost double the price of my liner. Wish I could find some of that foil so I could make my own kit.

 

[woodchopper]

Getting this permitted / inspected?

Because you said this I called my insurance agent and building inspector myself instead of relying on what my BIL said about permits and inspections. My insurance agent was pretty decent but the building inspector wasn't very helpful. Unless I can find a way to cover the present mantle this stove is going to stick out 2"-4" too much according to the code he was using. Any ideas or am I at the end of this stove ever getting used again. We really wanted to use this stove because it belonged to my late FIL. If someone can pull a rabbit out of their hat right now I'd really appreciate it. OTOH I'm glad I hadn't ordered the chimney liner yet. I guess it could be worse.

 

[drdoct]

I'm not sure what you mean by covering the mantle, but you could make a heat shield. All you would need is a little sheet metal then brake it to match the mantle bottom. Get 6 or so little ceramic donut washer things and screw the sheet metal to the mantle with the washer between them. I would run this by your inspector though because there really isnt any use doing anything unless it's ok with big govt. There are also heat shields that go above the stove and deflect the heat just past the mantle. To me, they look a little funky, but to others it's acceptable. Again, it all depends on the man.

 

[woodchopper]

There are also heat shields that go above the stove and deflect the heat just past the mantle. To me, they look a little funky, but to others it's acceptable. Again, it all depends on the man.

Thanks for the reply. I'd like to run this heat shield thing you speak of by the town code guy. I've never seen one of but would appreciate a photo of one if you know where on the web I could find it. I don't care if it looks hideous as long as it's legal. I could probably take it off after heating season and reattach it the following season. Sounds like it might be worth pursuing.

 

[drdoct]

https://www.hearth.com/talk/threads/9613/