New install questions

[Promod117]

Hello Everyone!


Been reading a lot of great info on this site. Replacing my Cemi Concept II with an Osburn 2200 and had a couple of questions. Late 70's house in NE Ohio. Chimney is external on south side, approximately 20-22 feet, 10" sq flue. Running a 6" double wall stainless liner.

There are two different Roxul products (at my local retailer.) Safe N Sound and Comfortbatt. The Safe N Sound appears to be more for fire resistance but doesn't advertise any R value. I would think that the Safe N Sound has to have some R value to it. Does anyone know? Or is there a preference? Both seem to be fire resistent. Couldn't find anything specific on Roxul's site.

I have used the Safe N Sound around the liner where it goes through the damper and packed that area pretty well. Also considering an additional block off plate.

Is there any reason to leave an air space between the original firebox and the insert?

If the air space is desirable, then what about sealing the opening where the face plate will go (as shown in my photo.)

Last question for the moment...What about filling the void between the new liner and the original flue with Roxul? Good idea or bad?

Thanks for any input!

 

[bholler]

Hello Everyone!


Been reading a lot of great info on this site. Replacing my Cemi Concept II with an Osburn 2200 and had a couple of questions. Late 70's house in NE Ohio. Chimney is external on south side, approximately 20-22 feet, 10" sq flue. Running a 6" double wall stainless liner.

There are two different Roxul products (at my local retailer.) Safe N Sound and Comfortbatt. The Safe N Sound appears to be more for fire resistance but doesn't advertise any R value. I would think that the Safe N Sound has to have some R value to it. Does anyone know? Or is there a preference? Both seem to be fire resistent. Couldn't find anything specific on Roxul's site.

I have used the Safe N Sound around the liner where it goes through the damper and packed that area pretty well. Also considering an additional block off plate.

Is there any reason to leave an air space between the original firebox and the insert?

If the air space is desirable, then what about sealing the opening where the face plate will go (as shown in my photo.)

Last question for the moment...What about filling the void between the new liner and the original flue with Roxul? Good idea or bad?

Thanks for any input!

Well first off what is meant by double wall liner? Are you talking about a pre insulated liner or the 2 ply smooth wall stuff? I would strongly recomend against the 2 ply stuff. It is the least durable liner on the market.

 

[Promod117]

Well first off what is meant by double wall liner? Are you talking about a pre insulated liner or the 2 ply smooth wall stuff? I would strongly recomend against the 2 ply stuff. It is the least durable liner on the market.

Thanks for the reply. I was just trying to give a little background on my install. To answer your question, yes, it is smooth inside. I haven't seen or read any pros or cons until your reply. Enlighten me, please.

 

[bholler]

Thanks for the reply. I was just trying to give a little background on my install. To answer your question, yes, it is smooth inside. I haven't seen or read any pros or cons until your reply. Enlighten me, please.

The 2 ply smooth wall stuff has a very thin inner layer that is unsupported on the bottom edge. This means it kinks very easily leaving a pucker on the inside which will fet snagged by a brush causing further damage it simply is not durable at all. If you want smooth wall go with mid weight or heavywall liner.

As far as the damper area goes you will want to make a block off plate out of sheet metal with safe and sound above it. You will also want your liner to be insulated for safety and performance reasons

 

[Promod117]

The 2 ply smooth wall stuff has a very thin inner layer that is unsupported on the bottom edge. This means it kinks very easily leaving a pucker on the inside which will fet snagged by a brush causing further damage it simply is not durable at all. If you want smooth wall go with mid weight or heavywall liner.

Thanks for this info. I can't go back now, (already installed) but I did notice what you're describing and will be careful when cleaning. I also read the manufacture does not recommend a metal brush (probably for the exact reason you've described.)