I have a 12ft 6'' flex liner inside of a 8'' original metal pipe which is inside of a 10.'' I did not put a liner around the flex as I felt the short run being straight inside of the others would not likely make a difference. I have no problems with draft at any time. Would I see a benefit regardless. Please feel free to start the CONSTRUCTIVE critique! :cheese:
Do I need one?
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regency said:
Are you saying that you did not wrap insulation around your liner?
From the description of your existing chimney, it sounds like
you're now venting a stove or an insert thru a zero clearance (ZC)
fire place.
If this is the case, you need to insulate your flex liner.
The ZC venting is not rated for the temperatures that
your flex liner can reach, & therefore does not have adequate
clearance to combustibles.
No point in burning your house down.
It has an additional 6'' flex inside of the original 1989 built house chimney. It seems to be an overdone setup with the diameter of the 10'' followed by 8''. Are you telling me that with three layers of metal with the gapping as stated I run any sort of a risk? This is my second season with this setup burning nearly 24/7. I have little creosote buildup due to shorter pipe. Hope people chime in cause now i'm questioning myself which I rarely do! :gulp:
I believe it may have been a zero clearance. I will check following posting, What I had was your typical fireplace you see everywhere, without any stonework, just a metal box with fake stone for a backing. black top/bottom with a fan to blow around, glass acordian windows. etc etc.
Yep. A ZC fireplace. That chimney and the framing around it were never designed to take the heat coming off of a wood stove liner. In use as a fireplace there was enough cooling air sucked in the inside pipe and around it between it and the outside pipe to cool it. Not with a wood stove liner.
I have contacted several installers/companies throughout my area who state everything is good with my install. They agree that venting the stove directly into the old 8'' is not safe. I have the 6'' flex sealed on the stove running up to the top. This now makes three walls of pipe opposed to the two with the zero clearance. No one says they insulate around the flex. Looking for more feedback! Maybe this is done in other states but not in Michigan? They all agree that an insullation wrap is needed in a masonry chimney but not a zero clearance.
I have the same ZC set up currently.
As I understand it (from posters here and various stove retailers) is that the ZC flu has got to go. You need to tear it all out and run Class A 2011 HT pipe all the way up.
As I understand it (from posters here and various stove retailers) is that the ZC flu has got to go. You need to tear it all out and run Class A 2011 HT pipe all the way up.
cycloxer
Minister of Fire
I can't tell you the rules, but I can tell you that everytime you put one pipe inside of another and then another, etc, you cut down on the heat transfer. This is how they make the hot zones in metal furnaces - they literally uses packets of metal sheet spaced off of one another to cut down on the radiation. It is tough to say how hot that third 10" pipe is actually getting.
cycloxer
Minister of Fire
If it stays that way when you run at max operating temps then you are probably fine. My forced hot water pipes get hotter than that (you can't touch them w/o burning your hands) and they go right thru my wood floors. I'm not saying it is legal, but I am saying that practically it's not going to burn anything down (which is probably why your shop said it is okay).
I'm not all that happy about having to tear out the existing flu and replacing it with $1200 pipe. I mean, logically it seems that it would be ok.
On the otherhand, every woodstove manual I've read specifically stated that 2100HT class a pipe is needed if not using a masonry chimney. Since the life of the stove/chimney is what 20-30-40 years I just want to do it right the first time. It will also make me feel alot better when loading up the stove before bed or work.
Buy the best and cry once I suppose...
On the otherhand, every woodstove manual I've read specifically stated that 2100HT class a pipe is needed if not using a masonry chimney. Since the life of the stove/chimney is what 20-30-40 years I just want to do it right the first time. It will also make me feel alot better when loading up the stove before bed or work.
Buy the best and cry once I suppose...
regency said:
I hear you. Probably will be ok but it's not up to code and the manuals are pretty specific as to venting options.
Can you take back the liner? Your probably only looking at a 3-400 difference after the tax credit. Spread that over 30 years of life and it's peanuts.
tfdchief
Minister of Fire
I have burned my Little Buck (26000) since 1982 in a Majestic ZC triple wall fireplace with no liner or direct connect. I just recently direct connected it to a SS 7" liner (uninsulated) up the existing triple wall flue. I have checked the outside of the triple wall many many times under all kinds of firing conditions and it has always been cold. When I started there was very little direction with regard to inserts. So being a fire fighter and an inspector, I evaluated my situation and proceeded cautiously, sort of testing a little at a time until I was comfortable with my set up. In the present, I have looked at many manufacturers installation specs on inserts rated for, and in ZC fireplaces as well as the codes and standards for such installs. I will admit that they are not as clear as they should be in my opinion, but I don't seem to find any that say neccessarily to insulate the SS liner, just that the insert has to be connected to a SS liner, all the way to the top of the chimney. Many say do not cut off any air circulating mechanisms that the ZC fireplace has, and I take that to include the triple wall flue. Every situation and install is different and without actually looking at at it, I would not be comfortable with advise. Just giving you my experience. I also know the new EPA stoves are quite different! You are obviously re-evaluating your situation and that is good. Those who are always concerned, observant, and cognisant of the perils of wood burning, usually don't have any problems. The ones who just blindly burn are the ones in my experience who have problems.
From the regency owners manual= Means must be provided to prevent room
air passage to the chimney cavity of the
fi replace. This may be accomplished by
sealing the damper area around the chimney
liner, or sealing the fi replace front. This I have done. It also states = 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 fl ue collar and the
chimney top. This I have also done. The only thing in question now is this = The factory-built fi replace must be listed per
UL 127 or ULC S610. I will look into this but I assume that it is good.
air passage to the chimney cavity of the
fi replace. This may be accomplished by
sealing the damper area around the chimney
liner, or sealing the fi replace front. This I have done. It also states = 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 fl ue collar and the
chimney top. This I have also done. The only thing in question now is this = The factory-built fi replace must be listed per
UL 127 or ULC S610. I will look into this but I assume that it is good.
cycloxer
Minister of Fire
Okay, here's the deal, legal issues aside:
You have a triple wall metal chimney. Ideally you want to maintain an equal air gap between each of the pipes. With no contact between them, you eliminate conducted heat. You can do that with 1" spacers or insulation. Now, you still have radiation between each metal pipe, but it gets cut in half with each layer, 6 to 8 to 10 (or 12 whatever it is). Just make sure your piping runs straight and true and you have no hot spots. I am not surprised that the temperature is very low at the outermost pipe. What type of metal are the other pipes made of? Steel? Galvanized?
I haven't seen your install, but keep checking it out. Get the stove real hot, like 600-700 and go measure some more areas particularly around any wood bracing, wiring, anything combustible. Those are your problem areas. Personally, that is what I would do before I just junked all of that piping and spent big $$$ to replace.
If your liner is one continuous piece from the stove to the top of the chimney with no connectors, that is pretty damn safe right there.
You have a triple wall metal chimney. Ideally you want to maintain an equal air gap between each of the pipes. With no contact between them, you eliminate conducted heat. You can do that with 1" spacers or insulation. Now, you still have radiation between each metal pipe, but it gets cut in half with each layer, 6 to 8 to 10 (or 12 whatever it is). Just make sure your piping runs straight and true and you have no hot spots. I am not surprised that the temperature is very low at the outermost pipe. What type of metal are the other pipes made of? Steel? Galvanized?
I haven't seen your install, but keep checking it out. Get the stove real hot, like 600-700 and go measure some more areas particularly around any wood bracing, wiring, anything combustible. Those are your problem areas. Personally, that is what I would do before I just junked all of that piping and spent big $$$ to replace.
If your liner is one continuous piece from the stove to the top of the chimney with no connectors, that is pretty damn safe right there.
You just have to be more specific in your titles. Do I need one - well of course the answer is yes - do I need a atv, new stove, new toy, new chainsaw(s), new splitter ..... YES.
I have no idea about the liner, looks like you are getting a lot of help with that.
I have no idea about the liner, looks like you are getting a lot of help with that.
regency said:
Thank you! I can't believe that every person out there rips out all the old piping to install in a pre fab. I believe this is a safe set up. I called the county building inspector and he said follow the owners manual. The manual gives three different recommended chimney set ups with mine being the ideal. The outer pipe appears to be galvanized, not sure on the middle pipe. I can reach in and feel the metal shell five inches away is warm. The shell eight inches around that is cool to the touch. I don't want to tick anyone off but I think it is crazy to rip everything out when the manufacturer doesn't say to!
cycloxer
Minister of Fire
The goal is to not burn down the house. Every installation situation is different. The codes are written to try to accommodate all situations and they are not perfect. Just look at your combustibles and think about 'what if' scenarious. Worst case you can go get some 1" spacer rings and throw them around your liner to ensure that you have an equal 1" gap for the full length. Also, you could always add a layer of insulation wrap around your liner if you want to drop the temp even more.
Go work on some houses built in the 70's and you will see some scary setups that are still in use. In general, the installations and materials available today are light-years ahead in terms of safety.
Go work on some houses built in the 70's and you will see some scary setups that are still in use. In general, the installations and materials available today are light-years ahead in terms of safety.
cycloxer
Minister of Fire
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