Liner question

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

burntime

New Member
Hearth Supporter
Aug 18, 2006
2,395
C'mon hunting season!
Hello all,

My Hampton was installed (finally) yesterday. Is there any issue with the liner touching 1 side of the masonary as it goes up the chimney? What about the opening at the top of the masonary firebox? Last, the guys up and left and told me wait 48 hours to lite it? Does the gsket material take time to dry or ?

Thanks as always
 
Liners rarily go completely straight unless spacers are used. Not that big of an issue should it touch. But a wavy liner produces more friction and impeeds draft. Another question how do you know it touches the flue? Did you remove the damper block off plate?

That's right a damper block off plate is code required to prevent intrusion of air that not only draws heat from the living space but also cools that flue liner. Cooling the flue liner again impeeds draft and cooling excellerates Cresote build up.
Please explain your install. Aslo read you manual about intrusion of air in the flue line read the manual about liner insulation and also the liner's manufactures specs about spacing and insulation.

On the HI3000 many installers smear furnace cement on the Flue collar connector. That might be the reason for the 48 hours? Even that is a little lame as the stove heat would cure it. Please detail your observations and post here I think you need guidence o and some good advice. the 48 hours from the installers is a new one for me.
 
I have a full masonary chimney in the middle of the house with a 13x13 terracotta flue. They removed the damper, installed the stove attaching the liner at the stove and a flashing at the top. Then they calked the flashing at the top to the terracotta. Before they put the surround on I looked up the chimney with the old mirror trick to inspect. I asked about insulation etc at the bottom and they said the flashing will eliminate any down draft from arround the stove and with the 6 inch liner that I would be very pleased with the draft when compared to my old 1980's stove. Sorry to ramble...am I making sense on the install?
 
Hi -

I'm in the process of installing into a 13"x13" tile. Elk has been most helpfull in pointing out the code and practical requirements.

Carefully read the stove and liner owners manuals. The block off plate is required at the bottom of the chimney. If present it would have prevented your mirror inspection. Sound like they need to come back and finish the job.

Many liners also specify that they need insulation to qualify for the UL listed performance. Read carefully. Insurance and inspector aside, performance is also enhansed by insulating.

ATB,
Mike P
 
I think chances are even if they had made & installed a block-off plate you're better off making your own and getting rid of what was there. Most made ones are poorly designed, in my case it was leaky and too small. Granted, anything is better than nothing. I'm not a fan of the "sealing only at the top", and as mentioned I think it has to be sealed at the bottom or it's not up to code if the installation instructions say so but... I'm not the expert on that. The reason I'm not a fan of the top only seals is because my top seals broke in the beginning of winter, and I was not going to go up there on my roof in winter to fix it, that's dangerous. My block-off below was the only thing stopping the constant air from sneaking down the broken seals up top and into my living area 24x7 or go the other way around, my heated house air from rising out the flue and sneaking out around the broken seals at the top. The block-off should also make your unit more efficient, the heat rising will hit the lower blockoff and find it's way into the living area instead of rising and losing it to the chimney, it's safer too if you have a chimney fire. As mentioned, you shouldn't be able to take a mirror and look up, you should see a piece of sheet metal.

Here's how to build your own. It's the one I'm building right now, you probably want to look in the "Gear" forum where we're discussing a 2 piece block-off. At this point, if you disconnect your liner you have to push it UP to get it off your Hampton and that UP action usually means the whole liner lifts up breaking the seals at top. If you do the one piece block off and do lift it up and break the seals at the top, silicone doesn't adhere to itself so, you'd need to scrape all the silicone off and then reapply high temp silicone. For the cover plate it's best to silicone the bottom and push it down onto the chimney crown so silicone oozes out the sides. Same with the storm collar, it's best to silicone underneath it and push it down onto the cover plate til the silicone oozes out the sides. This pdf, on page 6 shows a picture that explains what a cover plate is, and storm collar if you're not familiar. Yours may or may not look similar up there. In the end, do what it takes and get the lower block-off. You'll probably be best following those instructions and doing it yourself, maybe your liner has give and won't break the seals up top lifting it off.
 
Burn time. I promised I would not go off but your installation is the reason I have a job, to protect the consumer from poor workmanship and getting ripped off.
I would make damn sure your liner was HT 2100 and installed exactly according to the liner's specs.

I would demand to have this info or atleast the manufacture and model ## and look up the instalation requirements and hold the installers responsible to installing it as such.

direct cut and paste from page 6 of your manual

I suggest you read your manual especially page 6

4. Installation must include a full height listed
chimney liner type HT requirements (2100
degree F.) per UL 1777 (U.S.) or ULC
S635 (Canada). The liner must be securely
attached to the insert flue collar and the chimney top.

2 Solid-fuel Inserts in Factory-built
Fireplaces.
1) The insert must be tested and meet the
Check your local building codes - Building
Inspection Department. You may require
a permit before installing your insert. Be
aware that local codes and regulations may
override some items in the manual.
"

5) Means must be provided to prevent room
air passage to the chimney cavity of the
fireplace. This may be accomplished by
sealing the damper area around the chimney
liner, by This is required by code for a damper block off plate

 
Sorry to kick a dead horse but to clarify...a full stainless liner from unit to top of the chimney with a sealed plate on top only is NOT sufficient in a full masonary chimney?
 
Ahaa, page 6 says you can do the blocking plate OR seal the face of the unit. They used insulation all around the surround. Is this still not sufficient. Again, I am not confronting...I want a safe install as well.
 
The installers didn't put in a block off plate because the manual neither calls for one nor recommends one. Hampton only shows the installation of a block off plate for direct connects to the first flue tile. Not for full liners.

Which, by the way, is how the manuals read for 99% of the inserts I have seen. I don't know where this business keeps coming from about having a bottom block off plate for inserts with full liners, sealed top plates and surrounds that are sealed against the front of the fireplace.

And that surround is going to stop a flashback just as well as a block-off plate. Probably better.

Ain't no inspector. Just a guy that reads a lot of installation manuals.
 
elkimmeg said:
Burn time. I promised I would not go off but your installation is the reason I have a job, to protect the consumer from poor workmanship and getting ripped off.
I would make damn sure your liner was HT 2100 and installed exactly according to the liner's specs.

I would demand to have this info or atleast the manufacture and model ## and look up the instalation requirements and hold the installers responsible to installing it as such.

direct cut and paste from page 6 of your manual

I suggest you read your manual especially page 6

4. Installation must include a full height listed
chimney liner type HT requirements (2100
degree F.) per UL 1777 (U.S.) or ULC
S635 (Canada). The liner must be securely
attached to the insert flue collar and the chimney top.

2 Solid-fuel Inserts in Factory-built
Fireplaces.
1) The insert must be tested and meet the
Check your local building codes - Building
Inspection Department. You may require
a permit before installing your insert. Be
aware that local codes and regulations may
override some items in the manual.
"

5) Means must be provided to prevent room
air passage to the chimney cavity of the
fireplace. This may be accomplished by
sealing the damper area around the chimney
liner, by This is required by code for a damper block off plate


Quote it all Elk:

"This may be accomplished by
sealing the damper area around the chimney
liner, or sealing the fireplace front."
 
So there is disagreement in the house of Hearth? Am I ok or not? My gut is that it is sufficient but this is my 1st new insert. I used to have and old cemi 2 1980s insert that vented directly into the chimeny. I never has a problem but did check the chimney every 2 months or so. How about some of the shop owner, installers type...Bueller, Bueller, anyone? I want to make sure that I am safe. By the way thanks a million for all that have responded so far.
 
Look at your manual. Then look at the installation. If the installation is in agreement with the manual, ya got a safe install.

Did the installers pull a permit for the installation and did an inspector sign off on it?
 
The fireplace co said that since I was replacing one with a new epa stove that it is not needed. Only if I am adding an additional one. Thats why I am wondering. I saw a thread earlier too that raised a ruckis (sp) that was similiar. I called my ins co and they told me the same thing that I don't need to modify my insurance policy since I was replacing an old insert. Only if I add a new (additional) burning appliance. The install does meets the hampton manual requirements by my reading.
 
Then I would just make sure that you have a good seal, usually three inch thick fiberglass strips, around that surround, test it for air leaks when you do a burn and enjoy your stove.

When my liner install was inspected I was dinking around with a blockoff. Inspector asked me why since my surround is four times thicker steel than the stuff I was using to make the blockoff. I tossed the piece of galvanized crap in garage for scrap metal.
 
the most important question is the liner is it HT 2100? this is spected by the stove manufacturer Is it UL 1777? T he last time I inspected the Hampton insert it was installed against a field stone facing gaps galore. Another part of the cut and past also pointed out requirements of code can superseed the instalation manual so there is not a pissing war speak to your inspector and confirm what he will accept. I can tell you without any hw=esitation Per National uniform code a permit is required. the insurance co has no jurisdiction concerning wavering national codes. Your manual tell you this I cut and pasted it. You have been informed, your town's inspectors may or may not want to get off their duff to do their duties and enforce and inspect per code. Get that documented. If this install occured in my town and I knew about it I would be going to bat for you calling the installers and guestioning them about their practices they know permits are required for installations. Its spected in the very manual of the stove they are installing. After that there would be a damper block off plate. What installers or people that question code don't know is that the proof is not up to me to produce but up to them. My question then becomes show me where in code the damper block off plate is not necessary?

11 years later no one has found supporting code to over rule the blocker plate omission. If I lived near enough to BB and helped him with his liner install, I would have installed a blocker plate I would have arrived with the sheet metal and tapcons tin snips and refactory caulk RTV caulk and taken care of it. Rhome also mentioned the reflective value of the blocked plate if sealed top and bottom is that not creating a dead air space? Is not a dead airspace a form if insulation?. Part of being a suscessfull inspector is being consistant code enforcement is the same for all Had you stopped by my office and pulled a permit I would have told you what I will be targeting during my inspection As it stands you want clarification about an illegal install. Without a permit there should be no insert installation to discuss. Don't believe me? May be BB can supply the code word concerning an appliance change out according to NFPA 211? Everything here is for discussion and education oppinions advice. In usa we have freedom of speech it is ok to dissagree. Your inspector may accept insulation strips around you suround as a proper seal but untill he is asked you should not burn you insert for 48 hours given by the very mouth of an installer that knows he installs illegally without permits. Got to ask is this one to place your safety and trust in?
 
elkimmeg said:
the most important question is the liner is it HT 2100? this is spected by the stove manufacturer Is it UL 1777? T he last time I inspected the Hampton insert it was installed against a field stone facing gaps galore. Another part of the cut and past also pointed out requirements of code can superseed the instalation manual so there is not a pissing war speak to your inspector and confirm what he will accept. I can tell you without any hw=esitation Per National uniform code a permit is required. the insurance co has no jurisdiction concerning wavering national codes. Your manual tell you this I cut and pasted it. You have been informed, your town's inspectors may or may not want to get off their duff to do their duties and enforce and inspect per code. Get that documented. If this install occured in my town and I knew about it I would be going to bat for you calling the installers and guestioning them about their practices they know permits are required for installations. Its spected in the very manual of the stove they are installing. After that there would be a damper block off plate. What installers or people that question code don't know is that the proof is not up to me to produce but up to them. My question then becomes show me where in code the damper block off plate is not necessary?

11 years later no one has found supporting code to over rule the blocker plate omission. If I lived near enough to BB and helped him with his liner install, I would have installed a blocker plate I would have arrived with the sheet metal and tapcons tin snips and refactory caulk RTV caulk and taken care of it. Rhome also mentioned the reflective value of the blocked plate if sealed top and bottom is that not creating a dead air space? Is not a dead airspace a form if insulation?. Part of being a suscessfull inspector is being consistant code enforcement is the same for all Had you stopped by my office and pulled a permit I would have told you what I will be targeting during my inspection As it stands you want clarification about an illegal install. Without a permit there should be no insert installation to discuss. Don't believe me? May be BB can supply the code word concerning an appliance change out according to NFPA 211? Everything here is for discussion and education oppinions advice. In usa we have freedom of speech it is ok to dissagree. Your inspector may accept insulation strips around you suround as a proper seal but untill he is asked you should not burn you insert for 48 hours given by the very mouth of an installer that knows he installs illegally without permits. Got to ask is this one to place your safety and trust in?

That was beautifull elk. ;-)
 
Whenever I look online for NFPA 211 & block-offs, they're only brought up with direct connects and I don't see mention of it for full liners. I couldn't find it in his install manual either, it mentions block-offs with direct connects or factory fireplaces which he has neither. There are a lot of insert manuals that don't mention or show block-offs with full liners. They usually show the direct connect method with a block off plate saying it's illegal in Canada, then show a full liner install and no block-off or mentioning of it which I find odd if it won't pass without it.

The Hearthstone Clydesdale is the only insert I've seen that specifically states a block-off is required even with full liners and masonry fireplaces and states it in a picture as well. I think it because the Clydesdale although rare can be installed in such a manner that will put its heat coming out well behind the surround. Not going to be any good there, a block-off will be your only saving grace if one is dumb enough to keep the Clydesdale in that configuration.

A block-off should be put in regardless. Better efficiency, safety reasons, the unit will run better, if the seals break up top, I'm a big fan of them but I just want to clarify because I don't see it in his manual the mentioning of a block-off with full liner in a masonry fireplace, and anywhere I see NFPA 211 mentioned with them, it's direct connect installs.
 
I am pretty much done with the subject but I do know that the only NFPA item addressing the issue I have ever been able to find is:

"12.4.5.1 Paragraph 8 - Means are provided to prevent dilution of combustion products in the chimney with air from habitable space."

For direct connects that means is a sealed block-off plate. In the case of stoves and inserts vented into masonry chimneys with full liners and sealed top plates it is a draft issue. You need to keep the cool room air out to maintain flue temp for a good draft. With a freestanding stove vented into a liner you do it with a block-off plate. With an insert, there are two ways to do it. One can be tested for leaks with the stove burning, sealing the surround, and the other cannot, a block-off plate.

Even the Clydesdale manual says you can do it either way:

"The surround must be sealed to the fireplace front or the
damper area around the chimney liner must be sealed to
prevent room air from entering the chimney cavity of the
fireplace."
 
BrotherBart said:
I am pretty much done with the subject but I do know that the only NFPA item addressing the issue I have ever been able to find is:

"12.4.5.1 Paragraph 8 - Means are provided to prevent dilution of combustion products in the chimney with air from habitable space."

For direct connects that means is a sealed block-off plate. In the case of stoves and inserts vented into masonry chimneys with full liners and sealed top plates it is a draft issue. You need to keep the cool room air out to maintain flue temp for a good draft. With a freestanding stove vented into a liner you do it with a block-off plate. With an insert, there are two ways to do it. One can be tested for leaks with the stove burning, sealing the surround, and the other cannot, a block-off plate.

Even the Clydesdale manual says you can do it either way:

"The surround must be sealed to the fireplace front or the
damper area around the chimney liner must be sealed to
prevent room air from entering the chimney cavity of the
fireplace."

BB,

Just now saw this as I'm considering how I'm going to install my own insert...as with your manual, the manual for the C450 Jotul also say you only need the block-off plate with a direct connect.....but, as a mechanical engineer, I believe that lack of a block-off plate and no insulation on the liner is an accident waiting to happen. Consider this example: your liner fails during a chimney fire and, with no insulation, some of the the gases rush into the chimney area...gas rises so they go upwards and hit the top plate which is sealed.......more gas comes out the liner sidewall and tries to go up but is pushed downwards towards the insert....and with no block-off plate installed, it rushes around your surround and into your room...........

Now consider an insulated liner and block-off plate: you have a fire and it burns through the pipe.....it encounters the insulation which may or may not contain it but it is your first line of defense which you presently don't have if your liner isn't insulated...then some gases fill the chimney area and rise, encounter the top plate and are pushed downwards but they encounter a well sealed lower block-off plate which partially or completely stops the flow of smoke. This is your second line of defense which you also don't have unless you have a lower block-off plate installed....so what I think Elk is saying is "better safe than sorry"......I know when I do mine, I'm insulating the liner (25 ft of 1/2" insulation costs $250) AND making a block-off plate is not too difficult (material for the plate is very low cost and the hearth.com web page shows how to make one).....insulation plus a block-off plate are peace of mind if you ever burn unattended.....
 
I have never argued against installing block off plates cast. I have argued with saying that they are required by the building codes. They are not. And aren't even recommeded by most installation manuals for fireplace inserts.

Three point harnesses and helmets would be a good thing while driving a car too. No question about it. But they aren't required by law or recommended by car makers.

FYI: My stove is a free standing unit sitting in the fireplace with a blockoff plate and two feet of rockwool insulation sitting on top of it.
 
Not only can't I quote code, after Elk did such a good job, I don't think I have to. Whether or not a block off plate is 'required' or not didn't make any difference to me; I installed one. It makes sense to me that it enhances both the safety and performance of my insert installation.

In theory, with a full stainless liner, sealed at the insert and at the top of the chimney should direct any flue gasses directly out. Up...UP...and away; that's theory. Cast made the perfect 'what if' point and we've seen it written in other threads; what happens when a part of the system fails? Recently, one failure at the collar on the insert caused a CO backup. Another probably faulty installation blew the face plate off of the insert all together. A block off plate will not guarantee that these things cannot occur, but will cut down on the probability and provide another line of defense. Plus, it's much easier to effectively seal the area at the block off than the face plate (IMHO).

How many of us wood/coal/pellet burners have smoke and / or CO detectors installed in our homes, beyond what is required by code? What about fire extinguishers? And why? Because they add a level of safety and peace of mind while we enjoy a cocktail by the nice toasty fire. Not to mention that the cost and effort to provide that level of safety is reasonable and absolutely justifiable.

The consensus usually ends up being that whether it's required or not is not the issue. It's an inexpensive, easy to add safety measure that just makes sense. Blocking flue gasses from backing up into the living space, blocking heat loss up the chimney, creating a dead air space for insulation, etc....

my .02
 
Rhonemas, Thanks for the blocker advice I am currently designing a piece to fit into my installation. I have a few questions for you or any one else with an opinion. why does the blocker plate sit up so high in the fireplace. I was going to go right off the top lip of my opening since i could drill and tap the plate that is there. here are some images of my plans thus far.

do you have the blocker up next to the old dampener so that you have enough room to get the liner over the stove?

is it bad to screw the plate into the bricks? i guess i can see them cracking is the grout a better place or should i just seal it with silicone and be done with it.

I was going to make it out of .125 stainless plate any issues with that?

Thanks for any help provided
 

Attachments

  • [Hearth.com] Liner question
    blocker2.webp
    58.8 KB · Views: 356
OMG this is an oldie but a goodie thread! Amazing what you can learn over time!
 
wow it is old i didnt notice the "2006" your on to bigger issues at this point.
 
Status
Not open for further replies.