Good Day, was just wondering if with a 22' 6 inch stack, has anyone ever required two dampers? Is that possible?
Dave
Dave
Anyone ever require 2 dampers in their flue?
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kennyp2339
Minister of Fire
Thats me, I roll w/ (2) 6" dampers, damper 1 is a flue collar damper adapter made by duravent (dvl pipe) damper 2 is a regular damper that is inserted in the dvl pipe about 30" above the stove collar, damper 2 is my primary damper, mainly because thats above where I did my original draft test with a meter.
My stove calls normal draft at .05wc ft while running at high, when I tested my draft I was .18 to .20 so just over 3 times the recommended draft, with damper 2 shut my draft gets down to .06 - .08 while on high, I also had a whistle at my flue collar with the high draft, nothing but silence with the damper closed (this was before I installed a tight adapter fitting between the stoves flue collar and the duravent adapter collar)
Damper 1 gets used maybe twice to 3 times a year, really only when we get a strong Nor'easter will I partially close that one, I'm pretty well versed with fire behavior and my stove to know when I need a little more turbulence to fool my draft.
If I were to do it all over again, or maybe when I change my black pipe in a few years, I would avoid the flue collar damper, instead I would drill a hole about 6" above the flue collar for the meter to go into (hole can be used for a chimney temperature probe. Then above that I'd install (1) damper then go 18" above that for the second if needed, you may need to spread the difference if your black pipe is telescoping, I have a 60" long telescoping section so I only installed the one (poor measurement) and due to that location I poorly chose, if I wanted to add another one I would not be able to telescope the dvl properly.
My stove calls normal draft at .05wc ft while running at high, when I tested my draft I was .18 to .20 so just over 3 times the recommended draft, with damper 2 shut my draft gets down to .06 - .08 while on high, I also had a whistle at my flue collar with the high draft, nothing but silence with the damper closed (this was before I installed a tight adapter fitting between the stoves flue collar and the duravent adapter collar)
Damper 1 gets used maybe twice to 3 times a year, really only when we get a strong Nor'easter will I partially close that one, I'm pretty well versed with fire behavior and my stove to know when I need a little more turbulence to fool my draft.
If I were to do it all over again, or maybe when I change my black pipe in a few years, I would avoid the flue collar damper, instead I would drill a hole about 6" above the flue collar for the meter to go into (hole can be used for a chimney temperature probe. Then above that I'd install (1) damper then go 18" above that for the second if needed, you may need to spread the difference if your black pipe is telescoping, I have a 60" long telescoping section so I only installed the one (poor measurement) and due to that location I poorly chose, if I wanted to add another one I would not be able to telescope the dvl properly.
Can you explain your chimney setup and if any 90's.
I have the duravent damper at the base and the draft hole about 1.5 inches below the damper just enough so it doesn't swing into it.
Once I dialed my stove to .08 my burn time changed and stove won't creep past 750 anymore...
Do you get and smoke from the dampers on reload...I read an article they cause like a 15 percent obstruction even when open.
I had 2 on the chimney at my old house but that chimney was almost 40'. At 22' I doubt you will need 2
N.E.K. - D.D.S.
Member
All this effort to get good draft... and you guys have too much draft. Funny.
I have what feels like super strong draft on my little Jotul 3 TDIC-2. It is burning hot and clean, with almost no creosote (half way through season I got about a teaspoon out of it, as opposed to 6 gallons from my wood furnace which was installed incorrectly by previous owner's goons).
Anyway, I wonder if I have too much draft on the jotul... and if a damper might help.
I have what feels like super strong draft on my little Jotul 3 TDIC-2. It is burning hot and clean, with almost no creosote (half way through season I got about a teaspoon out of it, as opposed to 6 gallons from my wood furnace which was installed incorrectly by previous owner's goons).
Anyway, I wonder if I have too much draft on the jotul... and if a damper might help.
kennyp2339
Minister of Fire
Im straight up 22 - 23ft, my issue is that I live on top of a hill, I did a lot of extensive tree removal work so it really opened up my yard, below me is a swamp that runs about 5 - 6 miles across with no tree's and prevailing winds blow from the swamp to the hill, hits the hill (about 300ft vertical ft rise from the swamp) and dumps at my house, so i always have some type of pressure difference that contributes to the higher then normal draft.
kennyp2339
Minister of Fire
I'll be more then happy to sell you some of my extra "wc's ft's.
OH_Varmntr
Burning Hunk
I ran 2 dampers on a 20' out and up chimney on my Hearthstone Heritage. I always meant to measure the draft but never got around to it. A lot of control with the 2 dampers though.
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My Hearthstone Heritage IV TruHybrid Model 8024 Install
I picked this stove up Friday morning and began installation. Purchased the stove with a rear heat shield, ash tray and outside air adapter. Outside air kit being drop shipped in a week or so as they didn't have one in stock. Flue is up and out as seen below, 20' up to a rain cap from the...
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With 2 dampers do you see a dirtier chimney or any difference in cleaning schedule.
When I run my damper the pipe near the adapter area runs colder than normal but still within the 250 internal range....this will be my first year running a damper and burning almost 24/7.
When I run my damper the pipe near the adapter area runs colder than normal but still within the 250 internal range....this will be my first year running a damper and burning almost 24/7.
Thanks for all the responses to the OP. I have not measured my draft, but with single damper closed and air supply closed, the stove still seems to want to run away after a fresh load. The control with the single damper install helped 50-60% of the time, I was just wondering what else I can do. How do you properly measure with the manometer? There is a 1/8 inch hole the flue for my probe, and there is a 1/8 hole in the top right side of the firebox that holds the analog CAT gauge. Do you use these holes? I will also goggle a bit, but I think you guys are the pros I trust. I mentioned measuring to the dealer I bought the stove from, and he had no idea. I no longer use him.
Owners Manual: "draft between 0.06" and 0.1" WC. For drafts above 0.1" WC, install a stovepipe damper"
Thanks.
Dave
Owners Manual: "draft between 0.06" and 0.1" WC. For drafts above 0.1" WC, install a stovepipe damper"
Thanks.
Dave
kennyp2339
Minister of Fire
Draft is measured in the smoke pipe after the flue collar but before the T location, you will need a normal sized fire with the stove running on high for accuracy.
Understood, but how do you use the tool? Guess I don't understand what I need. Drill a new hole and fill with SS screw insert?
kennyp2339
Minister of Fire
Ashful
Minister of Fire
My chimney is over 30 feet straight up, 6" smooth wall insulated liner. I have no trouble holding .05" WC with the stove on a high setting in any weather, with a single damper. I'm wondering if there's a difference in design between my damper and kenny's, that he's needing two dampers to hold .05" on less pipe than me, or if maybe he's trying to hold .05" WC on some thermostat setting below the highest. My stoves only spec < .06" on highest setting, with .05" on highest setting being the ideal target.
Mine is a standard hardware store cast-iron plate on a pivot with a spring for friction. It has a few small holes, so it's never 100% closed tight. It just barely holds .05" WC in cold weather, for the week or two after any mid-season cleaning, but it does the job. Usually, by the time we hit our coldest weather of the season, a little seasonal chimney dust is built up on those tiny bypass holes, and I can get it to hold as low as .03 - .04", if that were my aim.
All dampers pretty much have the same volume in the holes. But I imagine some fit the pipe tighter.
Thanks Kenny, that is what I was needed to better understand. Is there a certain type of manometer or manufacturer/model I need to get to be sure the probe of the meter fits the diameter of the temp probe? How do you be sure that it fits tight? Sorry for the elementary questions. Have not done tihs before, but believe I need some firm numbers to dial in this stove. Thanks again!
My chimney is over 30 feet straight up, 6" smooth wall insulated liner. I have no trouble holding .05" WC with the stove on a high setting in any weather, with a single damper. I'm wondering if there's a difference in design between my damper and kenny's, that he's needing two dampers to hold .05" on less pipe than me, or if maybe he's trying to hold .05" WC on some thermostat setting below the highest. My stoves only spec < .06" on highest setting, with .05" on highest setting being the ideal target.
Mine is a standard hardware store cast-iron plate on a pivot with a spring for friction. It has a few small holes, so it's never 100% closed tight. It just barely holds .05" WC in cold weather, for the week or two after any mid-season cleaning, but it does the job. Usually, by the time we hit our coldest weather of the season, a little seasonal chimney dust is built up on those tiny bypass holes, and I can get it to hold as low as .03 - .04", if that were my aim.
[/QUOTE]
That's pretty good...what gauge do you have and what is the draft before turning to .05..
Mine is a standard hardware store cast-iron plate on a pivot with a spring for friction. It has a few small holes, so it's never 100% closed tight. It just barely holds .05" WC in cold weather, for the week or two after any mid-season cleaning, but it does the job. Usually, by the time we hit our coldest weather of the season, a little seasonal chimney dust is built up on those tiny bypass holes, and I can get it to hold as low as .03 - .04", if that were my aim.
[/QUOTE]
That's pretty good...what gauge do you have and what is the draft before turning to .05..
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