Sealing of a surround?

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hunterpa64

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Hearth Supporter
Jan 24, 2010
42
Pa
When my installer put in my 1402 he cut a hole in the damper and ran the liner, wrapped up through. At the top of the chimney he stuffed high temp insulation down a few feet and then poured some cement like seal over top. Capped it with a cover and of course the flue cap. The liner is wrapped almost the whole way down wit a high temp blanket and mesh screen. It's in an old oversize masonary flue so there is definitely space around it.

My question is now after the fact, he didn't block the damper or form a plate as I read the instruction manual suggests. It also syas in lieu of that metod that you can seal the surround? How does one go about that? Isit really needed with the top side sealed 100%? I'm kinda lost on this one and could definitely use some opinions and solutions or am I ok with the way it it? My main conern with any ideas are safety 1st then efficiency after.
 
It's probably a fine installation but that liner should be blocked off at the damper area. If it was me and it was after the fact, I would buy some rock wool and just pack it in real right around the pipe and would feel fine with that. Well, I would probably call the shop that installed the stove and ask them why they didnt do it and if they would mind coming back and doing it for free.
 
The installation if properly done, is probably very safe. However, a damper block off plate may significantly improve heating efficiency, especially if this is an exterior chimney.
 
It's an interior chimney. Talked to the installer, needless to say not very happy I question his work. He wants to put insulation in above the damper, the same stuff he wrapped the flue with, 2000 F. Should I insist on this being done?
 
I would try out the stove for at least a week or two and see how it works. It could be a non-issue. In some cases the warm masonry of the interior chimney gently releases the heat as the stove cools down.
 
A good portion of my chimney is in my brrrr cold attic. Won't the cold air come down when my fireplace isn't running and likewise my oil heat go up the flue? Seems like it takes awhile for my blowerst come on steady when starting from scratch, would that be because I have to heat all the area up the chimney rather than just the cavity around the stove?

So again, is that high temp insulation wrap ok to use? It is wrapped around the flue so I'm assuming it's ok? If not let me know, he's scheduled to reluctantly come back and do this instead of pulling the stove and fashioning a plate. He reasons that the plate will be noisy due to expanding and contracting?

I just want it done right, safe and efficient. If I knew how to do it I wouldn't have hired a "professional".
 
Yes, high temp insulation would work, like the rockwool Franks suggested or kaowool. Just don't use regular fiberglass.

Personally I would pay them to install a proper blockoff plate if this is a concern. It is often hard to achieve a snug seal by just stuffing material in the damper opening.
 
I don't know if it's needed or not, I'm a customer not an installer. What I know is on the ID plate and in the instruction manual it specifically says that means of preventing passage of room air into the chimney cavity must be provided by either sealing the damper or the surround. Why is that specifically noted if it is optional?

If I paid for an install shouldn't it be done to specs?

I shouldn't have to tell the contractor how to read the installation manual and interpret it for him. It's frustrating to have to spec out the job and pay for it as well.

I do appreciate all the info you guys provide us less experienced people and if I come off direct I certainly don't mean to direct any negativity towards you all who have been so helpful. I just am about fed up with all the complications on this job that I paid good money for.
 
Ok, contractor agrees to putting a block off plate. He still insists it is not needed but I'd feel better knowing that the job is aligned with the installation manual, should I god forbid have any problems down the road.

Here's the description of his plan, please offer your insight guys.

A 2 piece stainless sheet attached to angle tapped into the chimney. I suggested sealing the edges with furnace cement. On top of the plate will be high temp blanket insulation. Around the flue connector he is leaving a 1" gap in the shield as well as the blanket. The 1" gap will be sealed with 2700 F cement. Sound ok?

Also, around my surround there are large gaps. I shouldn't have a need to seal these if the damper plate is a positive seal, right? If one was going to seal the surround how would you do it? Insulation? Would you remove the surround and attach the insulation to it or the face of the original fireplace? High temp blanket, foil backed? What adhesive would you use to attach it?

Should I have some type of document from him stating that it meets all applicable codes for my insurance company?

Hopefully one of you can help me out with the answers within the next 2 days before the work is completed. I really don't want to have this guy have to take time away from his schedule again to get the job done. He's actually a super nice guy and I feel bad causing the extra overhead, but I want to be 100% in line with the specs so I get 0 crap from my insurance inspector.
 
hunterpa64 said:
Ok, contractor agrees to putting a block off plate. He still insists it is not needed but I'd feel better knowing that the job is aligned with the installation manual, should I god forbid have any problems down the road.

Here's the description of his plan, please offer your insight guys.

A 2 piece stainless sheet attached to angle tapped into the chimney. I suggested sealing the edges with furnace cement. On top of the plate will be high temp blanket insulation. Around the flue connector he is leaving a 1" gap in the shield as well as the blanket. The 1" gap will be sealed with 2700 F cement. Sound ok?
2PC S.S. good, no separate mounting angle needed. He can just bend flanges on the stainless perimeter and tapcon it to the masonry. High temp silicone the perimeter to seal is fine.
Around the liner, I'd leave more like a 3/8" TO 1/2" gap, and fill it with a pc of regular stove rope gasket wrapped around and tucked into the gap. A 1" or even 1/2" gap filled with high temp cement/furnace cement is only goint to crack & fall out when the plates expand & contract, Guaranteed.


Also, around my surround there are large gaps. I shouldn't have a need to seal these if the damper plate is a positive seal, right? If one was going to seal the surround how would you do it? Insulation? Would you remove the surround and attach the insulation to it or the face of the original fireplace? High temp blanket, foil backed? What adhesive would you use to attach it?
Once the block off plate is in, no sealing of the surround needed. Plus if you need to remove the surround for whatever reason, would be a mess after sealing or caulking.
Seriously not needed if installing a block off plate.


Should I have some type of document from him stating that it meets all applicable codes for my insurance company?
Dunno bout that one. Maybe get a document from local fire chief or code inspector, that is if you pulled a permit. If not, your insurance company may or may not consider a claim anyways. Call them and ask if they even need any paperwork. They may raise your premium.

Hopefully one of you can help me out with the answers within the next 2 days before the work is completed. I really don't want to have this guy have to take time away from his schedule again to get the job done. He's actually a super nice guy and I feel bad causing the extra overhead, but I want to be 100% in line with the specs so I get 0 crap from my insurance inspector.
 
I seal around the surrond with the high temp silicone sealent works great and you dont have to pull anything out.
 
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