How many Insulate the pellet stove wall thimble with fire rated insulation?

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Is your pellet stove wall thimble insulated?

  • Yes

    Votes: 4 28.6%
  • No

    Votes: 10 71.4%

  • Total voters
    14
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The Selkirk DT Masonry conversion kit for my basement stove made a huge difference in warming and drying out the burn air from the outside. Amazing!
 
Don, that is for an 8" wood stove? So an insulated thimble would benefit slightly. A wood stove must keep the flue gases as warm as possible, for as long as possible. But with wood, many people burn unseasoned wood. Very few people actually let there wood sit the required 2-3 years before burning.

As for pellet stoves? Pellets have a very low moisture content and can stand a lower flue temp. Insulating a liner on a pellet stove is not as big of a deal as a wood stove.

As is the thimble on a pellet stove? Silicone the pipe to thimble connection and call it a day.

Hi Dexter
That is for wood or pellet
I see your point Dexter in that keeping the flue warmer for wood stoves prevents creasote buildup and is not the case for pellet stoves.

My point is that keeping the flue warmer for pellet stoves keeps the flue cleaner longer because the ashes do not condense so quickly and make it out the exit of the flue pipe.

Also my point for bringing up the wood stove is that the Rock Wool insulation is NFI acceptable for use in insulating the fireplaces for wood stoves. Therefore it is also accepted for wood pellet stoves.

My main point is that the up and out venting I setup in the garage was real drafty and cold around the pipe coming through the thimble. Before I used silicone which does not have enough R value, I wanted to really stop any cold from coming in by using an acceptable fire rated insulation. Since Selkirk uses it for thimbles it must be acceptable. The fire rated, soundproof 5-1/2 inch Roxul I used is R24 which has got to be better than a very cold air space.

Thanks for understanding.
 
I sealed the pipe to the thimble with hi temp silicone and made sure there was nothing combusible around the outside of the jacket that penetrates the wall.

The free air spaces between the pipe and the outer jacket of the thimble affords a lot of insulation.

Snowy
 
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I sealed the pipe to the thimble with hi temp silicone and made sure there was nothing combusible around the outside of the jacket that penetrates the wall.

The free air spaces between the pipe and the outer jacket of the thimble affords a lot of insulation.

Snowy

That's fine Snowy,

The free air space does add more air to feed a fire! Smothering it with fire proof insulation is better!

I used the 2150 Deg F fire rated NFI acceptable fireplace insulation.
A little more work but keeps the room warmer.
See pics > > https://www.hearth.com/talk/threads...-pellet-stove-hearth-for-garage.104197/page-3

Just look at this video you may understand the properties of Rock Wool a little better! This is what I am talking about!
As they say in the video, "Have you ever seen a rock burn?"
Believe me after seeing this I feel much safer having my pellet pipe surrounded by rock wool than an air space! Wow! ! !

http://www.rockwool.co.uk/why rockw...oes it burn-c7-/does it burn-c7- wooden house
 
Don do you realize what you are doing and saying? You cannot under any circumstances stuff a whole wad of insulation into a space which it is not designed for. You could very well (or anyone else you is taking this advice) create a hot spot in the thimble and start a structure fire when you were actually just trying ti stop a draft through a tiny crack...which by many building code enforcement folks is supposed to be left WITHOUT silicone. mods...Please put an end to this thread before someone burns down their house.
 
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Don do you realize what you are doing and saying? You cannot under any circumstances stuff a whole wad of insulation into a space which it is not designed for. You could very well (or anyone else you is taking this advice) create a hot spot in the thimble and start a structure fire when you were actually just trying ti stop a draft through a tiny crack...which by many building code enforcement folks is supposed to be left WITHOUT silicone. mods...Please put an end to this thread before someone burns down their house.
What is wrong with using the Selkirk insulated pellet stove wall thimble? You cannot tell people not to use it! Silicone should also be used! Why do you dislike Selkirk? We are still waiting for an answer.

Are you also saying the tech in the video will burn that house down?
 
What is wrong with using the Selkirk insulated pellet stove wall thimble? You cannot tell people not to use it! Silicone should also be used! Why do you dislike Selkirk? We are still waiting for an answer.

Are you also saying the tech in the video will burn that house down?
Hello
smiley-eatdrink062.gif
 
someone correct me if I'm wrong, because I don't use the Selkirk product, but unless adding insulation to the annular space between the pipe and the thimble is expressly mentioned (as allowed) in the manufacturer's instructions for that thimble, then it is not allowed. Adding insulation can cause a buildup of heat where it isn't intended, and possibly cause a very dangerous situation. We don't use the Selkirk product, so I cannot comment from experience, but the licenses I hold basically prohibit me doing things that are not expressly allowed. I guess the negligible gain you *might* get in insulating the thimble really isn't worth the more likely *risk* you take in doing so.....

agreed- close the thread, lock it, delete it.....just like the Ash Can when the libs trip over things, like as of late......:eek:
 
I agree it may take time to change things for these new thimbles to be accepted. Only time will tell!
 
There is nothing wrong with using insulation when it is part of the listed product...but you or anyone else cannot and should not add insulation to a thimble such as the dude in the vid. He is wrong and not just with doing that but a few other things I noticed too. Not to mention he's installing a real piece of crap stove too. Perhaps the biggest no no.
 
What is wrong with Lennox Whitfield? Whitfield stoves have been around for a long time.
 
Selkirk makes an insulated thimble. Yes Don.

But they don't make one for Selkirk DT? Which is what everyone is getting at. You took a UL listed part (with NO Insulation) and added insulation. Thereby throwing its UL out the window.

If it came with Insulation? Fine. But you showed pics of you cutting a whole sheet. Therefore you added it to a thimbke that did not come with it? No.
 
"thimbke" is thimble in Russian.....at least I'm pretty sure.
 
My damn phone has to small of a key board! Was getting the Samsung Note 2 last week and decided to wait till the 31st for the new S4. Its only 1/4" smaller than Note 2 with added features :)

10 days and counting. Its gonna make me look so much smarter!! Prob not :(
 
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Hi Dexter

Yes, the Selkirk DT does not have an insulated thimble at this time. I hope they will have one soon. I would never advise anyone to stuff their thimble or install a thimble that is not factory original. Since it is possible to purchase an insulated thimble, it may be an idea in a real cold region.
In the meantime, Since my garage is so cold, I am trying some fire proof insulation in the DT thimble because it runs cooler within the 3rd wall and the insulation is outside the 3rd wall. I am doing a test and watching it closely here and will let you know the results.

However if you saw this video you may understand the properties of Rock Wool a little better!
As they say in the video, "Have you ever seen a rock burn?"
Believe me after seeing this I feel much safer having my pellet pipe surrounded by rock wool than an air space! Wow! ! !

http://www.rockwool.co.uk/why rockwool-c7-/fire resistance/does it burn-c7-/does it burn-c7- wooden house
 
Believe me after seeing this I feel much safer having my pellet pipe surrounded by rock wool than an air space! Wow! ! !

I am by no means an installer, mechanic, or anything else related to a pellet stove other than an end user. I also did NOT stay at a Holiday Inn Express last night. But I think you are still missing the point. It's not about the fact that the insulation cannot burn. It's about the fact that now the insulation is going to transfer heat to the thimble, and in turn the thimble will now transfer it to the wood of the home, thus causing a fire hazard. I think this is what everyone has taken issue with. That particular thimble that does not come from the factory with the insulation and may be designed with different material, thickness, etc. and may not be approved for that heat transfer as well. Unless you are a metallurgist or work for the company, you will never know. Until your shed burns down.
 
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Don do you realize what you are doing and saying? You cannot under any circumstances stuff a whole wad of insulation into a space which it is not designed for. You could very well (or anyone else you is taking this advice) create a hot spot in the thimble and start a structure fire when you were actually just trying ti stop a draft through a tiny crack...which by many building code enforcement folks is supposed to be left WITHOUT silicone. mods...Please put an end to this thread before someone burns down their house.

This guy Don, is a hack and he is dangerous with no concern for safety. I can't imagine him showing up to service someones stove. It's pretty obvious that he is the "laughing stock" on this forum. Just read his posts

It's not about the fact that the insulation cannot burn. It's about the fact that now the insulation is going to transfer heat to the thimble, and in turn the thimble will now transfer it to the wood of the home, thus causing a fire hazard. I think this is what everyone has taken issue with. That particular thimble that does not come from the factory with the insulation and may be designed with different material, thickness, etc. and may not be approved for that heat transfer as well. Unless you are a metallurgist or work for the company, you will never know. Until your shed burns down.

He (Don) is as dumb as rocks. He doesn't have to prove it anymore, everyone knows.


Here is my Don2222 favorite:

66434-77120a4b32cc5326451c0b8a53927_zpsaa9f0251.jpg


Hello

My friend gave me a great idea! This was his 1st draft! See pic below:

This would change this 55 lb hopper to atleast a 95 lb hopper!

Now wait before you say that is wood and combustible, let's think this one out.

You could use heavy gauge steel and weld the corners. Also have to notch the bottom.
But that is no longer an easy home project.

So how about using plywood covered with aluminum flashing?

Or

How about Cement Board covered with aluminum flashing for protection against chipping and is fire resistant?

Now do you have any comments?


Tom C.[/quote]


He is so dangerous, he should not be allowed to post, only view.

Tom
 
If you go to seminars and classes, such as the one I just went to sponsored by Olympia Chimney Supply, there is often talk about technicians, sweeps, mechanics etc.. that run experiments in customer's homes. Kinda like insulating the air space in a thimble. Will doing this actually burn down someone's home? I don't know for sure, there are many variables...however; as professionals, we are bound by ethics to not "experiment" at a customer's expense. Filling a gap to seal out outside air may seem like logical thing to do. It can be disastrous under the right circumstances if the products you are using were not tested or designed with other materials, such as rock wool insulation etc...

Just look at this video you may understand the properties of Rock Wool a little better! This is what I am talking about!
As they say in the video, "Have you ever seen a rock burn?"
Believe me after seeing this I feel much safer having my pellet pipe surrounded by rock wool than an air space! Wow! ! !

While I haven't ever seen rock burn, though it can be melted under enough heat or pressure, I have seen rock get hot enough to actually catch wood on fire if the wood touches it. It's not about the insulation burning...it's about the transfer of heat from one surface to another. When you insulate something such as the annular space around the thimble you are in fact consolidating the heat from the pipe. Temps that may be 250::F on the surface could climb to 400::F or more and since there is no vent to allow the heat to escape it just builds...over time the surrounding area starts to pyrolically break down until such a time things go very wrong. If one had a chimney fire in the vent and temps rose up over 1000::F, the insulated area could climb well over 1500::F which is over the temp the pipe is actually designed to withstand and then the whole vent and or thimble starts to fall apart within the wall.

Don, if you are going to be doing installations, you ought to invest in some formal education aside from what you can troll up from the internet. It's no coincidence that more than 50% of the stoves I go to service are installed wrong and therefore need to be reinstalled properly before I can work on them.

NH doesn't require any licensure for solid fuel professionals...but, just because the State doesn't say so, that in itself is not a license for folks to go out and install whatever they want however they want. It is also not a coincidence that when a home burns to the ground in New England from a stove...NH homes seem to be more likely to lead the front pages of the papers.

I'm just coming at you from a competitors standpoint Don, but as a licensed and trained professional:

MA Solid Fuel Construction Supervisor #105742
NFI Pellet Specialist: #164362

What are your credentials?
 
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