Lopi Insert - chimney not sealed?

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cmonks119

New Member
Nov 10, 2020
7
California
Hello,

I recently purchased a home which has a Lopi Flex 95 installed. It was installed when the home was built in the early '90s.

My concern is that there is a small gap around the top of the insert flange, ranging from 1/8" to about 1/4". I will add a picture, you can see the gap directly above the damper control. The issue is that I can see through this gap, and there is no type of connection from the top of the insert up into the chimney. With a large fire going, I can actually see the flames going up through the damper and into the chimney. This is not causing any smoke in the house or anything due to the draft, but my concern is that it is also reducing the draft efficiency of the insert, as per the manual there should be an air-tight seal, forcing the draft to pull air through the appliance. In the user manual I see there are a few different installation methods, direct connection or positive connection with an adapter piece of pipe between the insert and the chimney, or a face-seal option where there is no seal at the chimney, but there is an air-tight seal around the face. It appears I don't have either.

I honestly don't know what is above the insert. I assume it is a direct pipe up to the roof, but obviously just doesn't have any direct connection to the insert. I don't know if there is a back-off plate or anything.

Anyway, looking for opinions on how important this is to fix (if at all), and what I should do about it.

My thoughts:
1. Is there any material I could purchase to 'stuff' in the gap? Perhaps I could get it close to air tight. Since it is visible it would have to be black to match and not look terrible.
2. Fabricate a ~1" piece of steel to bolt onto the existing flange and fill the gap to the outer surround? This shouldn't be too hard. Again I assume I should have some kind of insulation material to sandwich between the flange and the new gap filler piece to really make it air-tight. The insert insulation I have found so far mostly says 225 degrees, since this is directly above the damper I imagine it gets hotter than that?
3. Fix the chimney connection. Install a piece of pipe at the top of the insert up into the chimney, and install a back-off plate or attach to the piping if it exists? This of course seems the most involved. Assuming there is either piping or a back-off plate, could I do this without removing the entire insert?

Thanks for your help.

fireplace.jpg
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,487
central pa
What fireplace was the insert installed in?
 

cmonks119

New Member
Nov 10, 2020
7
California
It was installed when the house was built, so as far as I know the fireplace was 'made' for this unit. As you can see in the picture, there is about a 4" or so metal surround built into the fireplace that accepts the insert. It is bolted tight on the sides it looks like, just the top has this small gap.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,580
South Puget Sound, WA
Are you just seeing a little flame right in the center where the bypass rod meets the chimney liner pipe? The liner connection for this stove needs to be notched in order for the bypass rod to pass through the liner adapter.

As for the installation, the 1992 manual only says this stove is for freestanding use or masonry fireplace installation. I am not sure if they made a ZC cabinet for it at a later date.
 

cmonks119

New Member
Nov 10, 2020
7
California
Are you just seeing a little flame right in the center where the bypass rod meets the chimney liner pipe? The liner connection for this stove needs to be notched in order for the bypass rod to pass through the liner adapter.

As for the installation, the 1992 manual only says this stove is for freestanding use or masonry fireplace installation. I am not sure if they made a ZC cabinet for it at a later date.

No, I can see the full flame coming through the 8" damper (when the flame is that high). There is nothing above that top flange, I can see all the way to the rear of the fireplace across the full width through that gap. Unfortunately the gap isn't big enough for me to see what is up inside the chimney, all I can tell is that there is maybe a 8"x12" hole out the top of the fireplace into the chimney. The fireplace box and chimney are all masonry, I just don't know if there is any type of pipe or liner in it. I can't see what is above the fireplace, I'd have to wait for the fireplace to cool down and take some pictures up through the damper probably.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,487
central pa
No, I can see the full flame coming through the 8" damper (when the flame is that high). There is nothing above that top flange, I can see all the way to the rear of the fireplace across the full width through that gap. Unfortunately the gap isn't big enough for me to see what is up inside the chimney, all I can tell is that there is maybe a 8"x12" hole out the top of the fireplace into the chimney. The fireplace box and chimney are all masonry, I just don't know if there is any type of pipe or liner in it. I can't see what is above the fireplace, I'd have to wait for the fireplace to cool down and take some pictures up through the damper probably.
Can you show us a full pic of the install? And one of the chimney outside?
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,580
South Puget Sound, WA
Based on the description I would not burn until this installation is inspected by someone that knows what he is doing. There may be a fix with an insulated liner, but as described it does not sound safe. Your concerns seem valid.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,487
central pa
That really doesn't look like masonry structure. It looks like a veneered chase. Which could potentially be quite dangerous if not done properly
 

cmonks119

New Member
Nov 10, 2020
7
California
That really doesn't look like masonry structure. It looks like a veneered chase. Which could potentially be quite dangerous if not done properly

Yes the outside is a decorative rock, but behind that the fireplace and chimney are all brick and mortar, I can see it behind the insert and in the attic. It's not a red brick, but a beige, I'm assuming chimney type brick.

I suppose I'll call out a dealer and have them take a look at it.
 

RockyMtnGriz

Burning Hunk
Apr 19, 2019
122
SW Montana
Beyond the fire hazard, that is going to be pulling warm air out of the house and up the chimney 24/7, even if you don't use the stove.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,580
South Puget Sound, WA
The pictures help, thanks. Anything we say is a guess at this point. There need to be eyes on site. It could be they used regular stove pipe which is rotting away. Hard to say why , but it is wrong. I would pull the metal surrounding the insert for a clearer view so that one can see what is actually happening there.
 

cmonks119

New Member
Nov 10, 2020
7
California
Ok, got some new pictures up through the stove damper. It appears to me to be a clay chimney liner, do you concur? If that is the case, then it seems like my install is ok minus the small gap, making the face seal not airtight?

Assuming the chimney is ok, back to solutions for that air gap. Can I just use a high-temp sealant/cement to fill this air gap? I see some products for this purpose rated to 2000 degrees and for metal-to-metal. Seems like that would do it.
Or should I use a strip of steel to make a plate to fit tight over that gap? A strip of insulation sandwiched in between the plate and existing flange should fill the gaps and make it airtight as well, and still be removable for service of the insert in the future.

Thanks for your input.

IMG_2403.jpg IMG_2397.jpg manual.jpg
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,580
South Puget Sound, WA
This is what is known as a slammer install. It is no longer legal or according to code. Yes, that is a tile-lined chimney and it looks pretty clean. If you have been burning regularly in the stove, you are doing a good job.

Because this is a pre-EPA stove I am moving the thread to the Classics forum. Slammer installs should never be seen with modern stoves.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,580
South Puget Sound, WA
You are right. I just dug out the manual and find it is listed phase 2. My error. Hang on, heading back to the main forum with the thread. It is surprising that they had the slammer option in at that late date.