Duratech Pipe and Support box temps

  • 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.

p301

Member
Dec 1, 2016
128
NJ
So i just finished constructing my alcove and am getting ready to close up the ceiling and was hoping somebody here had some experience with the duratec pipe and temps that they run at before i seal everything off. I am attaching pics of my temperature readings at my round ceiling support box and the wood surrounding the box and just wanted to see if other guys are in the same ballpark with their temps. These were taken when the stove was running about 600 degrees (by the way its a lopi endeavor and i am using dual wall pipe to connect to the support box)
IMG_5793.JPG IMG_5796.JPG
 
Last edited by a moderator:
I can't tell how far away from the pipe you are in those pictures, the beam does spread however, so for the most accurate temps, you want to be pretty close. I wish I had my stove burning right now, or I'd give you my readings. Saying that, they look find to me.
 
thanks for reply sodbuster. i also shot the beam right up on the box and it was about the same. I never liked the way they force you to frame at the minimum clearance distance to mount the box. If i ever did it over again id use square tube and bolt the box to it
 
thanks armiandog. i believe pyrolysis can start to occur at around 200. I wonder how much of the 164 temp is from the heat radiating up which will be blocked when i close up the alcove with the ceiling and how much is actually transferring laterally from the pipe through the support box
 
thanks armiandog. i believe pyrolysis can start to occur at around 200. I wonder how much of the 164 temp is from the heat radiating up which will be blocked when i close up the alcove with the ceiling and how much is actually transferring laterally from the pipe through the support box


OK, so I did some experimenting tonight to see what type of temps I could achieve with my stove, chimney and support box. I did a hot reload with smaller chucks of Ash, and left the air wide open to drive as much heat as I could up the chimney. The stove was clacking and pinging pretty good, and the maximum stovepipe temperature I could get with the IR was 230F at the thimble, while the thimble itself was only 165F. Once I backed the air down, and went into a nice secondary burn on low fire, the stove pipe went to 142F and the thimble was 134F. Your readings seem very high to me, and I would certainly try to get an answer before enclosing it. I would note that I had my IR about 4" from the spot I was checking. Obviously we have different stoves and chimney manufacturers, but I would think Class A should be pretty close to another brand of Class A. Hopefully someone else can chime in as well. Regards.
 
Thanks for the over the top effort... How does your pipe come out straight up through the ceiling or straight up and then out the wall? 230 is about what my stovepipe was reading. The outside temp gets hotter when it enters that ceiling support box and then once its in the class A its around the temp that you were reading. I did notice the higher up on that box i shoot the temperature goes down. I wonder if i would benefit or if its even allowed to install 1 6" length of class A below the box. I emailed duratec two days ago with the pictures of the temps i was shooting and got this answer. Now if could just get them to answer the second half of my question. I still think the temp seems high though and it makes me wonder what it would be for the 2100 degree chimney fire. Hopefully i get some more responses here. I dont even know how i would go about changing it if it was defective


RE: round ceiling support box
  • CC
Message body

They said that was a typical heat measurement for near the couplings
You are OK….

From: Peter Calabrese
Sent: Tuesday, November 14, 2017 12:28 PM
To: Nick Bruce <[email protected]>
Cc: Marina Rozova <[email protected]>; Duravent Customer Service <[email protected]>; DuraVent Tech Support <[email protected]>
Subject: Re: round ceiling support box


Nick any word on the temp from the lab and on using the roof radiation shield in conjunction with a storm collar at the support box

Thanks
pete
From: Peter Calabrese
To: Nick Bruce <[email protected]>
Cc: Marina Rozova <[email protected]>; Duravent Customer Service <[email protected]>; DuraVent Tech Support <[email protected]>
Sent: Monday, November 13, 2017 5:34 PM
Subject: Re: round ceiling support box

Thanks nick the temp was 264?
Is it ok to put the roof radiation shield down to the round ceiling box and put a storm collar above it. I may want to add roxul to this area in the future and want it to function like an attic insulation shield. I cant use the attic shield because of the reasons listed below also the pipe is also already in, but i can split the radiation shield to fit over the pipe

On Nov 13, 2017, at 5:07 PM, Nick Bruce <[email protected]> wrote:

Sounds about right but I am checking with the guys in the lab.
Will call you back
 
Thanks for the over the top effort... How does your pipe come out straight up through the ceiling or straight up and then out the wall? 230 is about what my stovepipe was reading. The outside temp gets hotter when it enters that ceiling support box and then once its in the class A its around the temp that you were reading. I did notice the higher up on that box i shoot the temperature goes down. I wonder if i would benefit or if its even allowed to install 1 6" length of class A below the box. I emailed duratec two days ago with the pictures of the temps i was shooting and got this answer. Now if could just get them to answer the second half of my question. I still think the temp seems high though and it makes me wonder what it would be for the 2100 degree chimney fire. Hopefully i get some more responses here. I dont even know how i would go about changing it if it was defective

My pipe goes through (2) 45's before going straight up through the thimble. It does cool slightly after each 45. I don't see why you couldn't put a section of class A below the box, mine is class A black all the way down to the stove. Might account for your higher temps.


RE: round ceiling support box
  • CC
Message body

They said that was a typical heat measurement for near the couplings
You are OK….

From: Peter Calabrese
Sent: Tuesday, November 14, 2017 12:28 PM
To: Nick Bruce <[email protected]>
Cc: Marina Rozova <[email protected]>; Duravent Customer Service <[email protected]>; DuraVent Tech Support <[email protected]>
Subject: Re: round ceiling support box


Nick any word on the temp from the lab and on using the roof radiation shield in conjunction with a storm collar at the support box

Thanks
pete
From: Peter Calabrese
To: Nick Bruce <[email protected]>
Cc: Marina Rozova <[email protected]>; Duravent Customer Service <[email protected]>; DuraVent Tech Support <[email protected]>
Sent: Monday, November 13, 2017 5:34 PM
Subject: Re: round ceiling support box

Thanks nick the temp was 264?
Is it ok to put the roof radiation shield down to the round ceiling box and put a storm collar above it. I may want to add roxul to this area in the future and want it to function like an attic insulation shield. I cant use the attic shield because of the reasons listed below also the pipe is also already in, but i can split the radiation shield to fit over the pipe

On Nov 13, 2017, at 5:07 PM, Nick Bruce <[email protected]> wrote:

Sounds about right but I am checking with the guys in the lab.
Will call you back
 
sodbuster i do feel a little better now that i got it from two sources but it still seems hot to me. i'll look in to checking out putting in some durablack below the connection. It still baffles me how they force you down to the minimum clearance to mount the box. I had 16" OC spacing that i could have made even bigger and they force me to frame a 12x12 box to install the ceiling support just seems dumb to me
 
sodbuster i do feel a little better now that i got it from two sources but it still seems hot to me. i'll look in to checking out putting in some durablack below the connection. It still baffles me how they force you down to the minimum clearance to mount the box. I had 16" OC spacing that i could have made even bigger and they force me to frame a 12x12 box to install the ceiling support just seems dumb to me

I can't disagree with you on that.
 
so do you think adding a 1' length of duratec below the box would move that hot spot further down the pipe so its further away from the ceiling or do you think the support box would still be the same temperature. I don't mind doing it but i don't want to do it if it wont make a difference
 
so do you think adding a 1' length of duratec below the box would move that hot spot further down the pipe so its further away from the ceiling or do you think the support box would still be the same temperature. I don't mind doing it but i don't want to do it if it wont make a difference


I wish I had a section of single wall in my system to tell what happens to the temp at the transition, but I don't. Common sense says it would move it down, but I would wait a day or so for Duratec to give you their final answer. Remember, it's deer season, and a lot of guys are off right now. I wouldn't button it up permanently yet. I'd do some temporary block offs and burn away for now though. I think if I were to replace a section, it would be to replace as long of one as possible to eliminate all your concerns.
 
its not single wall its DVL which is their double wall pipe that pipe stays about about 220 when i have a good fire burning hot. Ceiling support box where it sticks down into the room is where i got that 264 reading it is hotter than the DVL pipe at the connection point and cools off as i move up its 3" length.

I sent duravent the picture and they confirmed with the lab that the temps were ok.. I think im going to cut a hole in my wifes closet so i can shoot from the top down into the box and see what the temps are inside the box where its mounted against the wood. (this is going to go over really well) i tried to get in there from next to the stove but thought i was going to burn my legs off!

PS Don't remind me its deer season its killing me to be inside screwing around with this instead of being out there
 
its not single wall its DVL which is their double wall pipe that pipe stays about about 220 when i have a good fire burning hot. Ceiling support box where it sticks down into the room is where i got that 264 reading it is hotter than the DVL pipe at the connection point and cools off as i move up its 3" length.

I sent duravent the picture and they confirmed with the lab that the temps were ok.. I think im going to cut a hole in my wifes closet so i can shoot from the top down into the box and see what the temps are inside the box where its mounted against the wood. (this is going to go over really well) i tried to get in there from next to the stove but thought i was going to burn my legs off!

PS Don't remind me its deer season its killing me to be inside screwing around with this instead of being out there

Sorry, I see that now, just keep telling yourself it'll be worth it in the end. 264 does seem hot, but I doubt Duravent would tell you it's OK in writing unless they were pretty certain. Just screw some OSB us there temporarily, and get out there for the evening hunt.
 
I had the same concern about the temperature of the portion of the round support box that extends 3 inches below the ceiling after the installation of my stove. I called the duravent tech support number and they said that reaching 250 degrees F was nothing to worry about. I would think the temps where the wider portion above the ceiling ( touching the framing )would be quite a bit cooler.
 
sorry up i didn't see that you responded to the thread. The part that sticks down was the same area that i was concerned about. I called too and they said it was fine. The wider portions to see quite a bit cooler. Even as you move up the piece that sticks down the temps start at about 250 and get down to about 199 around the trim piece. I closed up the ceiling last night i put roxul in the framing but wasnt sure weather or not i should stuff it around the ceiling support box. I think i am leaning towards not what do you guys think. Here is a picture of the ceiling box and the stove install so farIMG_5822.JPG IMG_5828.JPG
 
sorry up i didn't see that you responded to the thread. The part that sticks down was the same area that i was concerned about. I called too and they said it was fine. The wider portions to see quite a bit cooler. Even as you move up the piece that sticks down the temps start at about 250 and get down to about 199 around the trim piece. I closed up the ceiling last night i put roxul in the framing but wasnt sure weather or not i should stuff it around the ceiling support box. I think i am leaning towards not what do you guys think. Here is a picture of the ceiling box and the stove install so farView attachment 216223 View attachment 216224


Looks really nice, especially with the fire going! :) I have the same type of install, I finished mine with a solid piece of wood, and now regret it. I would like to have access to that area, for inspections if nothing else. What are you going to finish the Durock with on the ceiling of the alcove?
 
Thanks . I know i wish i had access too. I might end up putting a hole in my wifes closet and frame out a little door to stick my head in every so oftem to look in. The part that is above the attic i guess i will never see again!
I wanted to finish it with a piece of sheet metal painted the same black color as the stove but i want to reflect heat not gather more of it so i may end up hammering some copper for up there too its a shame to waste the money on something i cant see really but i would have enough left over to make the small still i always wanted!
 
We have the same setup, straight up DuraTech with DVL stovepipe. The only difference being we have a slight offset in the stovepipe for when we switched to the T6. You might want to add a probe flue thermometer. Surface pipe temps on double-wall are not that helpful. I tend to watch flue temps more than I watch stove top temps when running the stove.

We're heading into a warm spell for a few days so the fire will not be running 24/7, but I can take IR readings at the same locations once I can have a vigorous fire burning. I have access on the top side too and can take a reading there if necessary. Ping me after Thanksgiving to remind me to check. FWIW, our system has been in place since 2006 without any issues.
 
Thanks begreen i ended up making an attic insulation shield after the support box was up i didnt like the exposed wood joist above the height of the support box so now i have insulation at two levels in my chase do you think i should put some in those open edges around thr box or leave it and just put the trim piece up
 
Will the cement board be getting a tile, metal or copper surfacing before the trim collar goes on? That would cover those edge gaps. If so I'd probably leave it empty, but no harm if you want to fill the open edges with some roxul.
 
Thanks . I know i wish i had access too. I might end up putting a hole in my wifes closet and frame out a little door to stick my head in every so oftem to look in. The part that is above the attic i guess i will never see again!
I wanted to finish it with a piece of sheet metal painted the same black color as the stove but i want to reflect heat not gather more of it so i may end up hammering some copper for up there too its a shame to waste the money on something i cant see really but i would have enough left over to make the small still i always wanted!

I think if I had it to do over, I'd use the Durock like you did, smooth the seams with thin set, and leave the right panel as is, then paint the entire ceiling flat black. Nobody will ever notice, unless their standing with their manhood about 3" from 600 deg steel. Not a good time to be critical of someones installation. ::-) You could use fine head trim screws for any trim along edges, easy to remove.
 
  • Like
Reactions: begreen
I think copper begreen id like to do black galv sheet but i dont want that surface any hotter than need be.

Sodbuster can you post a picture of your install im curious. the problem with durock that i have found is its so fragile and isnt good for repeated screwing and handling. i had to get access to some areas that i sealed off. the multi tool cuts it pretty well in place but it will toast a 30 dollar blade in no time for me a little door in my wifes bathroom closet will work best
 
I think copper begreen id like to do black galv sheet but i dont want that surface any hotter than need be.

Sodbuster can you post a picture of your install im curious. the problem with durock that i have found is its so fragile and isnt good for repeated screwing and handling. i had to get access to some areas that i sealed off. the multi tool cuts it pretty well in place but it will toast a 30 dollar blade in no time for me a little door in my wifes bathroom closet will work best


Here's my install, colors are a little off for some reason, the board that is black and forms the entire ceiling of my alcove is not removable without cutting and prying, it was tacked up with a finish nailer between day one and day two of the install. I would like to have a full access panel where I could climb right up in there if necessary. The framing for my chimney support could hold up a small army, the installer commented on it. Said he wished every job would be as prepared and well built as mine, I love overkill.


20171121_193119.jpg 20171121_193320.jpg
 
Last edited by a moderator:
Sharp lookin install does the tile make a protected surface with an air gap or is it right on the wall? What pipe and what stove? If that ceiling is just wood maybe you can snap some lines to make a square and cut it out with a multipurpose tool put some hinges and a bolt latch. After all the work i did i was pissed i payed someone to install it was the easiest part of the whole job!