UL 103HT chimney damper

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Ul 103-ht is a rating for a chimney system not connector pipe or dampers or anything like that. It is just the chimney and the mounting and shielding components. So no there is no ul-103ht chimney damper and with most modern stoves there is no need for a damper at all
 
Hmmm ok then i see that i really thought it was just the chimney system not connector pipes that was covered by ul-103. I stand corrected.
 
I'm talking about something that installs in between sections of insulated double-wall chimney pipe, not adjacent to the stovepipe. What about that?
 
I have never seen that and don't know why you would ever want to do it anyway. What stove are you looking to hook up how tall will your stack be?
 
My stack should be about 21' tall. I want a damper at the top of the conditioned space to prevent unconditioned air from getting into the chimney when the stove is idle.
 
That is not necessary at all. Just shut the intake on the stove and you will loose very little air. Also dampers slow down flow create turbulence and make it a pain to clean so uncles you need one to control overdraft you shouldn't put one in. Another thing is any listed damper can not shut the flue off completely
 
What about a damper at the very top, under the cap? Maybe with a cable that runs down to the stove?
 
I guess you could do a top sealer if you could find one to fit i have never seen one. But it is totally unnecessary. And i am not sure where you would run the cable to in order to be able to secure it. It sounds like allot of complication to fix a non issue
 
Think about it: All of the other vents (except plumbing) in a house have or should have dampers for energy efficiency reasons when the devices they serve are idle.
 
Yes but you can close the inlets on the stove yes modern stoves don't close all the way but with out a fire in there creating strong draft there will only be a tiny amount of air moving though the chimney. Believe me it is not an issue
 
Yes but you can close the inlets on the stove yes modern stoves don't close all the way but with out a fire in there creating strong draft there will only be a tiny amount of air moving though the chimney. Believe me it is not an issue

Perhaps, but just how much and whether it is "tiny" compared to other leakage through the house is apt to depend on the stove and installation, the house it's in, and how cold the outside air is. In my case, I have an OAK directly connected, a very tight and superinsulated house, and I wanted to limit/eliminate as much unwanted/uncontrolled air leakage through the house as possible. So in my installation I placed an ICC damper section (UBD; http://www.icc-rsf.com/main.php?t=chem_produits&i=37&l=en) up just below the ceiling above the stove. I had a welder close off the openings in the damper plate (I think the letters ICC were cut into the plate, as a minimum flow area) before I installed the piece. I run the damper either wide open during a burn or completely off (the next morning). I didn't like the thought of a cold column of air settling down the chimney and leaking out into the room more than I'd get otherwise. But I don't have any measurements on how this line of thinking actually is working, and since I can feel a tiny amount of cold air leakage around the stove's air controls when the stove is not in use I'm wondering if I ought to put a damper at the wall where the OAK duct comes in.
 
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No matter what you are going to get some air around that damper probably as much as you get through the closes inlet so again i dont think it is worth it and it is against code to have a solid damper in the pipe. Just keep it burning and it wont be a problem lol.
 
Dick, is that UBD intended only for single wall stovepipe?

I couldn't quickly find my list of parts from 4-5 years ago, but I believe it was the UBD I got, mine was for double wall, and that's the only one ICC shows on their site. It's in their ULTRABlack line, which is all double wall stuff. The construction specs for the UBD says the wall thickness is about 3/8", which would indicate double wall anyway.

My thinking seems to be the same as yours, concern about what is going on when the stove is not in use. In my case, I'm apt to start a fire up around 5-6 pm, feed it wood as needed during the evening, and let it burn itself out, probably down to a few coals by midnight or so. First thing in the am I close the damper. It's not primary heat, although it does warm up the lower level nicely. I leave the thermostat down there at 65 through the winter.

bholler, I couldn't find anything pertaining to code that says there can't be a solid damper in the flue pipe, but I do note in at least one reference that these things are made with some open area, even when the thing is in the "closed" position. This is to allow at least some movement of flue gas through it. But I don't know if that is just a matter of design or code. If code, perhaps it is a local matter rather than something like IRC. Anyway, one quickly learns what happens when lighting off a fire in the stove if the damper is not open, or even if it is closed before all the coals have burned out and gone cold.
 
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Was the damper a ul listed part? if so you are not allowed to modify a listed part doing so violates the manufacturers instructions which is a code violation. And again you are going a long way to fix a problem that isnt really a problem you would be better of to just block off the small opening left in the intake when the stove is not in use then it would actually be sealed. But really how much air do you think you will loose through that tiny hole? The problem is if you close it to soon co could back up and if it is just coals there is not allot of odor left to give it away. There is a good reason listed dampers cant be solid.
 
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I have live coals in my stove for a very long time after it appears to have burned out. Closing off the flue completely doesn't seem to be a good idea from a CO l leakage standpoint.
 
I have live coals in my stove for a very long time after it appears to have burned out. Closing off the flue completely doesn't seem to be a good idea from a CO l leakage standpoint.

I agree, don't close the damper when there are live coals. Before I close the damper in the morning, I open the door and move the ashes with the poker. The way I burn, there are few mornings when there is anything live and I can't close things down. But others have different burning patterns and easily could get into trouble misusing a damper, whether it's one in the flue pipe below the ceiling or a cable-operated chimney-top damper.
 
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