Block Off Plate & Liner Question

[gstowe]

I've gleaned a lot of good info here on the subject issue. Now coming back for more specific advice to see if my sweep's counsel is based on thermodynamics or ... not.

Situation: Insert (good quality Regency unit) installed w/ masonry chimney on exterior wall. Chimney isn't lined. No insulation installed between insert and fireplace; i.e. insert just backs up into fireplace. Insert was installed with about an 18" length of 6" stainless pipe that extends through the old fireplace's damper "bracket" into the chimney, then a bunch of insulation shoved up around the cracks/crevices. My sense is this is NOT good, not if I want heat to heat the house.

I know what I've read here but here's my sweep's advice: No need for a liner - it'll be a lot of money for no heat gains. No need for a separate block off plate - shoving the insulation around the damper bracket serves the same purpose. Putting some insulation between the insert and fireplace brick may make some difference.

What I want to know: I'm obviously skeptical of the sweep's advice. He's the only game in a three-county area so please don't tell me to find another guy ... I'm rural enough where there aren't choices. I think maybe he's just trying to save me money. I think I want a different answer though. I'm thinking the liner & block off plate could make a BIG difference in the insert's performance. The block off plate is something I can do but the insert looks to be comparatively expensive; is the consensus that the liner isn't as important as the block-off plate? My chimney is 25' high coming through a steep-pitched roof ... can liners be installed from below - from inside the house - or do I need to rent a cherry-picker and install from above?

Thanks folks; appreciate all the advice that's shared here.

 

[bholler]

I've gleaned a lot of good info here on the subject issue. Now coming back for more specific advice to see if my sweep's counsel is based on thermodynamics or ... not.

Situation: Insert (good quality Regency unit) installed w/ masonry chimney on exterior wall. Chimney isn't lined. No insulation installed between insert and fireplace; i.e. insert just backs up into fireplace. Insert was installed with about an 18" length of 6" stainless pipe that extends through the old fireplace's damper "bracket" into the chimney, then a bunch of insulation shoved up around the cracks/crevices. My sense is this is NOT good, not if I want heat to heat the house.

I know what I've read here but here's my sweep's advice: No need for a liner - it'll be a lot of money for no heat gains. No need for a separate block off plate - shoving the insulation around the damper bracket serves the same purpose. Putting some insulation between the insert and fireplace brick may make some difference.

What I want to know: I'm obviously skeptical of the sweep's advice. He's the only game in a three-county area so please don't tell me to find another guy ... I'm rural enough where there aren't choices. I think maybe he's just trying to save me money. I think I want a different answer though. I'm thinking the liner & block off plate could make a BIG difference in the insert's performance. The block off plate is something I can do but the insert looks to be comparatively expensive; is the consensus that the liner isn't as important as the block-off plate? My chimney is 25' high coming through a steep-pitched roof ... can liners be installed from below - from inside the house - or do I need to rent a cherry-picker and install from above?

Thanks folks; appreciate all the advice that's shared here.

Your sweeps advice is wrong. Does not meet minimum code and could be quite dangerous

 

[bholler]

To install a liner (which should also be insulated) you will need to get to the top. In some cases it could be pulled up through but you would need to do that from the top.

 

[gstowe]

To install a liner (which should also be insulated) you will need to get to the top. In some cases it could be pulled up through but you would need to do that from the top.

Roger. I figured it had to be secured up there anyway instead of just shoved up from the bottom.

The flue itself is roughly 10" square. Once I get an insulated liner in there, is it important (or unnecessary) to insulate the remaining voids between liner and flue?

Yep, I recognize the sweep is wrong, but he's rather insistent that what I have meets code ... maybe that's because the chimney itself is in pretty good shape? I also recognize that codes are minimum safe requirements ... never hurts to go above & beyond. I'm after two things here: safety and maximizing heat in my house.

 

[Ctwoodtick]

Once you decide to get this install made to be proper, keep in mind the chimney will have to get cleaned really thouroghly. With the set up that’s been in there, the buildup of creosote could be really heavy and you’ll want that stuff out of there.

 

[Bushels20]

Gstowe,

If youre after safety and maximum heating efficiency, an insulated liner (all the way up the chimney) AND and a block off plate are a very good idea. Code aside, (which “bholler” is correct) your current setup is not safe.

The insulated liner is going to keep the (ideally) minimal smoke going up the chimney hot all the way up not allowing it to cool and condense into creosote on the walls of the liner . Without said liner, it is more likely that said (minimal) smoke will condense back into a solid (creosote) and cling to the flue tiles. A liner is just a more safe way to burn. Yes, it’s an expensive purchase.

The block plate is going to retain and maximize the heat your insert is producing by not allowing it to heat the brick of the exterior fireplace (first) prior to heating the interior of your home. I would insulate the top of the block plate and the side walls of the firebox itself.

 

[bholler]

Roger. I figured it had to be secured up there anyway instead of just shoved up from the bottom.

The flue itself is roughly 10" square. Once I get an insulated liner in there, is it important (or unnecessary) to insulate the remaining voids between liner and flue?

Yep, I recognize the sweep is wrong, but he's rather insistent that what I have meets code ... maybe that's because the chimney itself is in pretty good shape? I also recognize that codes are minimum safe requirements ... never hurts to go above & beyond. I'm after two things here: safety and maximizing heat in my house.

Your type of install can meet minimum code. But to do that the stub of liner needs to be positively attached to the clay liner. The clay liner can be no more than 3 times the volume of the stove outlet. And you need a properly sealed block off plate. This is assuming your chimney meets minimum code which most do not.

 

[gstowe]

Once you decide to get this install made to be proper, keep in mind the chimney will have to get cleaned really thouroghly. With the set up that’s been in there, the buildup of creosote could be really heavy and you’ll want that stuff out of there.

Roger that. Just cleaned today. This is the setup I inherited but it doesn't look too hard to do it right. Thanks.

 

[gstowe]

Your type of install can meet minimum code. But to do that the stub of liner needs to be positively attached to the clay liner. The clay liner can be no more than 3 times the volume of the stove outlet. And you need a properly sealed block off plate. This is assuming your chimney meets minimum code which most do not.

Again - thanks for taking time to give me the assist & explanation. The stub of that existing extension was just stuck through the damper bracket ... the only attachment was to the collar of the insert. It was the sweep who did the original install; he remembered it. Maybe this was code in 1965 when he was learning the business? Who knows. Don't worry, I'll get it fixed ... will order the liner & rent a cherry picker to get on top of that chimney.

 

[gstowe]

Gstowe,

If youre after safety and maximum heating efficiency, an insulated liner (all the way up the chimney) AND and a block off plate are a very good idea. Code aside, (which “bholler” is correct) your current setup is not safe.

The insulated liner is going to keep the (ideally) minimal smoke going up the chimney hot all the way up not allowing it to cool and condense into creosote on the walls of the liner . Without said liner, it is more likely that said (minimal) smoke will condense back into a solid (creosote) and cling to the flue tiles. A liner is just a more safe way to burn. Yes, it’s an expensive purchase.

The block plate is going to retain and maximize the heat your insert is producing by not allowing it to heat the brick of the exterior fireplace (first) prior to heating the interior of your home. I would insulate the top of the block plate and the side walls of the firebox itself.

Excellent feedback; thanks for the thorough explanation. I'm convinced ... I'll do the insulated liner, insulated block plate, and insulate the firebox walls.

Once I get an insulated 6" liner installed, is there a need to backfill around it to fill in the remaining void between liner and flue tiles? If yes, is there a slurry that's good for DIY, or could I just get vermiculite?

Again, much appreciated for the assist.

 

[bholler]

Excellent feedback; thanks for the thorough explanation. I'm convinced ... I'll do the insulated liner, insulated block plate, and insulate the firebox walls.

Once I get an insulated 6" liner installed, is there a need to backfill around it to fill in the remaining void between liner and flue tiles? If yes, is there a slurry that's good for DIY, or could I just get vermiculite?

Again, much appreciated for the assist.

No need to backfill

 

[Hogwildz]

Don't forget the block off pate.

 

[gstowe]

Don't forget the block off pate.

Roger that. Just getting in there today with my grinder to cut around the damper bracket ... this will make better room for 6" liner without having to ovalize. Then I'll fabricate the block off plate. Thanks Hogwildz.

 

[maple1]

I'm curious how he is getting the existing setup clean? Does the insert & stub get pulled out? Otherwise the loosened creosote would be piling up around the stub & on the insulation somehow.

 

[bholler]

I'm curious how he is getting the existing setup clean? Does the insert & stub get pulled out? Otherwise the loosened creosote would be piling up around the stub & on the insulation somehow.

The proper way to clean that setup but most people dont

 

[Hogwildz]

Roger that. Just getting in there today with my grinder to cut around the damper bracket ... this will make better room for 6" liner without having to ovalize. Then I'll fabricate the block off plate. Thanks Hogwildz.

Don't be afraid to make the block off plate in 2 pcs for easier install if needed.

 

[maple1]

The proper way to clean that setup but most people dont

Really curious how this goes. And what is found when stuff gets pulled out to do the liner install.

Sounds like a slammer install if I read right?

 

[bholler]

Really curious how this goes. And what is found when stuff gets pulled out to do the liner install.

Sounds like a slammer install if I read right?

No it is a direct connect which meets code if done correctly

 

[maple1]

Must be the way I'm interpreting & picturing it. Which is a stub shoved up thru a damper opening into a much larger masonry chimney with no direct connect.

 

[bholler]

Must be the way I'm interpreting & picturing it. Which is a stub shoved up thru a damper opening into a much larger masonry chimney with no direct connect.

What you described is a direct connect. A slammer has no connection at all it is just slid into the fireplace

 

[begreen]

Direct connect installation example

 

[maple1]

What you described is a direct connect. A slammer has no connection at all it is just slid into the fireplace

Yes it might be my interpretation. I was reading the stub was just stuck into the chimney with no plate or direct connection or adaptor. Only some insulation.

 

[bholler]

Yes it might be my interpretation. I was reading the stub was just stuck into the chimney with no plate or direct connection or adaptor. Only some insulation.

And that is typical of most direct connect installations. It is not right but it is how most are done. A slammer has nothing at all just an insert sitting in the fireplace. No pipe at all.

 

[begreen]

Yes it might be my interpretation. I was reading the stub was just stuck into the chimney with no plate or direct connection or adaptor. Only some insulation.

The technical description of that type of installation is - cheap, lazy hack.

 

[bholler]

The technical description of that type of installation is - cheap, lazy hack.

Yes but i would extend that to cover all direct connects even done correctly they are poor performing installs