Be aware that the Woodstock stoves are not ULC listed. You and I may not care they are not certified for use in Canada, but, my insurance company would not send me a letter saying they would give me a pass if there were ever an issue.
Rear flue exit VS Top flue exit
- Thread starter frankm1960
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Be aware that the Woodstock stoves are not ULC listed. You and I may not care they are not certified for use in Canada, but, my insurance company would not send me a letter saying they would give me a pass if there were ever an issue.
I recently learned that my fireplace insert was installed without the chimney being sealed off. There's a big gaping hole where heat from the stove can pass by the liner that's there. I didn't need to take the stove out to see this. I just took off the trim around the stove and shone a flash light up there and had a good look. Could this be why I don't seem to get much heat out of my stove ? Shouldn't the chimney be sealed off or does that depend on the stove/insert ? I would think it should be sealed off with some kind of non combustible material to prevent heat loss ? The pic is the best I can do without removing the stove.
The pic shows the left hand side. It's the same big gap on the right hand side. Tons of heat could easily pass up there.
The pic shows the left hand side. It's the same big gap on the right hand side. Tons of heat could easily pass up there.
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It's fairly common and not as big of a deal as some on this site would have you believe provided the top is sealed well. What happens is that apce between the liner and the old chimney warms up. It's going to happen anyway.
A blockoff plate is what is recommended at the top of your fireplace.
It is well sealed at the top of the chimney. There's cap that's secured in place by screws and silicon caulking. So I would think that's a good seal at the top.
I have seen some documentation and manuals that indicated the old fireplace flue should be sealed near the stove and they don't mention sealing at the top though. I wonder why they wouldn't specify that you could seal it on either end or both ends. Just throwing that out there. Here's what the cap looks like. If it's useful info anyone I could take another pic showing just how that cap is sealed to the chimney crown when I get up there to clean the chimney.
Would it be worth sealing it at the bottom as well ?
I have seen some documentation and manuals that indicated the old fireplace flue should be sealed near the stove and they don't mention sealing at the top though. I wonder why they wouldn't specify that you could seal it on either end or both ends. Just throwing that out there. Here's what the cap looks like. If it's useful info anyone I could take another pic showing just how that cap is sealed to the chimney crown when I get up there to clean the chimney.
Would it be worth sealing it at the bottom as well ?
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Is a block off plate the same thing as what they call a "non combustible seal" ? I could just fabricate something out of heavy sheet metal and fasten in place somehow ?
Well I think it is a pretty big deal when it comes to heat loss. I would do an insulated block off plate for sure. As well as insulate behind the insert.
Here is how to fabricate and install. The sheet metal gauge doesn't have to be heavy.
https://www.hearth.com/talk/wiki/why-damper-seal-is-needed/
https://www.hearth.com/talk/wiki/why-damper-seal-is-needed/
I noticed a difference once I put my block off plate in, I put roxul then made a plate out of sheet metal from Home Depot. Why heat the masonry flue, no ones gonna benefit from that unless there's some mice living up there.
Your 1000 degree (on the BK only 500) liner is in there, you're warming it up whether you like it or not. What you don't want is a flow of heated room air into the fireplace and out the top. Plug one end or the other and that flow stops.
Is your chimney blocked off at the top ? I know mine is because I re-installed it after I did some chimney crown maintenance. I screwed it back on and applied a couple thick beads of silicon caulking all around to really seal it. The original installer had used silicon caulking to seal it as well so I did the same... but I must admit I thought it was sealed to prevent water from coming in... I wasn't thinking of blocking the flow of hot air when the stove was in use.
Here's something else I noticed with my insert... how the heck do you connect the liner to it ? There's no room to see the connection let alone get your hands in there to connect them. This insert was installed by the previous owner and I did pay to have some one come in and re-connect the line to the insert and generally bring the whole system up to code. I wasn't around to see how he was able to make that connection. Right now I have the stove pulled out about an inch or so just so I could see what was going on. The liner is pretty flexible it seems and I don't think I damaged the connection. It would be nice though if I could reconnect it myself somehow just so I could confirm it's still good. Any one here install an insert before know how this is done ?
well we use ceramic wool insulation allot of guys here use roxul both work fine roxul is easier to get and a little cheaper but ceramic wool is ul listed for chimney insulation. although that shouldn't matter for a block off plate just for insulating the liner.
I fabricated and installed a block off plate and insulated around the liner, essentially filling up the area between the old clay flue and liner with roxul. The metal plate I installed serves to keep the insulation from falling down. It's not a perfect air seal but blocks it off quite well.
Since installing it I have learned that insulating around a stainless steel liner is against the code where I am, it wouldn't be insurable. The reason, I'm told, is the liner will over heat, expand and potentially crack... something like that. It could also just weaken in that area where I insulated and eventually break off during cleaning process.
Anyone have any comments on this ?
Since installing it I have learned that insulating around a stainless steel liner is against the code where I am, it wouldn't be insurable. The reason, I'm told, is the liner will over heat, expand and potentially crack... something like that. It could also just weaken in that area where I insulated and eventually break off during cleaning process.
Anyone have any comments on this ?
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Seems like someone is blowing smoke. Have them provide the code that says this. Insulating around a stainless liner is very common. Kaowool insulation jackets are standard and recommended by major sweeps organizations. Poured in insulation is also common. Why would Roxul be any different?
I didn't ask him for the code but I'm looking for it now. He didn't say roxul is the problem persay, just that insulating my SS liner with any type of insulation in general is a problem. The insulation causes the liner to over heat in the area where the insulation is. Over heating apparently weakens the liner.
actually liner insulation is recommended by just about all of the liner manufacturers and they are tested that way for their ul listings in order to get a zero clearance rating to the outside masonry. As far a roxul goes it is not ul lised for chimney insulation it is approved for blockoff plate insulation though. The ul listing and manufacturers instructions will trump any local code so it will not be a problem with code although i doubt that there is and code anywhere saying that you can not insulate it
The type of liner I'm talking about are those "flexible" stainless steel liners that can be slid down an old clay flew... great stuff for installing inserts into old brick fireplace... is that what you mean by liner ? I'm not sure of all the products that are out there is why I ask. In any case this guy I talked to seemed to think and insulation around these liners is not a good thing. I'll keep digging.
Here's the type of liner I believe I have, may not be the same brand but in all likely hood the very same..
(broken link removed to http://www.kent.ca/kbs/en/search.jsp?_dyncharset=utf-8&_dynSessConf=-7518348841066773341&question=stainless+steel+chimney+liner&_D%3Aquestion=+&%2Fatg%2Fcommerce%2Fsearch%2Fcatalog%2FQueryFormHandler.searchRequest.pageSize=10&_D%3A%2Fatg%2Fcommerce%2Fsearch%2Fcatalog%2FQueryFormHandler.searchRequest.pageSize=+&%2Fatg%2Fcommerce%2Fsearch%2Fcatalog%2FQueryFormHandler.searchRequest.saveRequest=true&_D%3A%2Fatg%2Fcommerce%2Fsearch%2Fcatalog%2FQueryFormHandler.searchRequest.saveRequest=+&%2Fatg%2Fcommerce%2Fsearch%2Fcatalog%2FQueryFormHandler.search=&_D%3A%2Fatg%2Fcommerce%2Fsearch%2Fcatalog%2FQueryFormHandler.search=+&_DARGS=%2Fkbs%2Fen%2Fincludes%2Fheader.jsp.searchForm)
EDIT: You are right about the insulation wrap. I did a quick look up and found the following.
(broken link removed to http://www.selkirkcorp.com/WorkArea/showcontent.aspx?id=7348)
Section 8.4 if you're curious.
So having a little roxul around my block off plate is likely not going to do any damage to my liner. The guy I was talking to either doesn't know (he's a local dealer) or is blowing smoke.
I'm glad I came here and asked about it.
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Yes that is the type i am referring to also i install 40 to 50 a year and insulate almost every one according to the manufacturers instructions. If you use the proper insulation that is speced by the manufacturer there will not be any problem they are all flexible enough to allow for the expansion and contraction of the stainless. Even the pour in type stays soft enough to allow for it. I do not know about canadian code specifically but from what i have seen it is pretty similar to us code in this area and the ulc listings are usually the same or slightly more stringent.
http://www.djsonline.com/linerinstall.pdf
here is a link to selkirks installation instructions it clearly says that insulation can be used in us and Canada in order to get zero clearance to the exterior of the masonry. Selkirk does not allow for pour in insulation just their wrap is approved.
here is a link to selkirks installation instructions it clearly says that insulation can be used in us and Canada in order to get zero clearance to the exterior of the masonry. Selkirk does not allow for pour in insulation just their wrap is approved.
I have never heard of a good stainless liner failing from having an insulation blanket. Sound like the dealer's salesperson was selling cars last week.
I think he saw me coming 
I checked the selkirk site. I'm convinced the roxul insulation around the block off plate is not going to cause any problems.
I'll light it up monday and see if the block off plate and insulation was worth the effort Fingers crossed.
I'll post my findings.
I checked the selkirk site. I'm convinced the roxul insulation around the block off plate is not going to cause any problems.
I'll light it up monday and see if the block off plate and insulation was worth the effort
Fingers crossed.I'll post my findings.
I think he saw me coming
I checked the selkirk site. I'm convinced the roxul insulation around the block off plate is not going to cause any problems.
I'll light it up monday and see if the block off plate and insulation was worth the effort
I'll post my findings.
Well I finally did a burn test. All the work to install and insulate around my new block off plate has not really paid off. There is no significant difference in terms or radiant heat coming off the stove. The stove works as before.
So I'm looking at replacing my insert with a regular wood stove this year or next.
Thanks everyone for all the comments and suggestions. I did learn a lot.
Those changes will not give you any more radiant heat but they will reduce the ammount of heat loss and keep the fife box around that insert warmer which will give more convective heat.
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