When is a damper needed?

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I've asked a similar question a week or two ago, and got mixed reviews. I've nearly gotton my stove dialed in, BUT, do I need a damper. I'm running 16' pipe dbl wall, and I feel like I may have too much draft. The oak is required for my application, so I feel I am losing alot of my heat up the chimney. Correct me if I'm wrong, but the air coming from my oak is controlled by my primary air control right? would a damper be suitable for a dbl wall? Thx, Brian
 
This is a question I've often wondered myself. When that draft control would be beneficial. When you've got a box full of roaring flames, would even a slight damper adjustment allow you to reclaim even more energy into the room and preserve your wood a little longer?
 
The reason I don't use the pipe damper is I cannot for the love of Pete remember to open it back up when reloading and starting the next day.
 
Newer EPA stoves were designed to run without one.
It's not a straight up shot to the flue anymore from the fire box and you need to keep the pipes warm.
That said some are installing key dampers that have really strong drafts when the owner feels he can't lower the fire enough with the primary air...or losing to much heat up the pipes ie: real high stack temps.
 
I am under the impression you do not put dampers in with an EPA type stove. OAK intake is only supplying your stove with combustion air from outside the structure. It may indeed provide more air to the fire box due to your home being more air tight. The place the stove gets air is not a heat loss issue. In fact you would loose less heat if your not using inside air to provide combustion air. I had a mobile home with an OAK for the free standing stove. The heat ability was much greater with than without. I had a month to see the difference.
 
I have a damper on my pipe about 3 ft. above stove. I do not use. After posting and getting advice I have decided to not use. But, the previous owner told me he used all the time.
 
Backwoods said:
I've asked a similar question a week or two ago, and got mixed reviews. I've nearly gotton my stove dialed in, BUT, do I need a damper. I'm running 16' pipe dbl wall, and I feel like I may have too much draft. The oak is required for my application, so I feel I am losing alot of my heat up the chimney. Correct me if I'm wrong, but the air coming from my oak is controlled by my primary air control right? would a damper be suitable for a dbl wall? Thx, Brian

Well, I put one in, even though my manual says one is not needed. For me its added insurance on a run away and it adds even more control. I use mine all the time, as soon as I start closing off the air I close off it off by a 1/4 turn. My flue maintains temperatures until the very end of the burn pattern. Plus it seems I keep more of the heat usualable and not going up the flue.
 
Hey chvymn99 I tried closing my flue like you just a little when lowering air. WOW! what a difference much hotter air coming off fan. You might have something here. I am going to try for a while.
 
I'm putting one in soon just for safety. I have over fired mine (30 NC) 2 times and was a little spooked to say the least. I had the oak shut completely down and the zipper looked like a blow torch. I went outside and even covered OAK inlet with foil. It took a long time to get it cooled down. I know, a stupid move on my part and nothing to do with the stove. I would hate for this to happen to my wife when I was at work. I bought the damper when I bought the stove but forgot to put it in but I can assure you, it's going in soon.
 
I would say for anybody who thinks they have too much draft, should have been using mine all the time but I was too hard headed and did not give it a enough time to learn how it reacted with the stove.
 
I think they are less than $10 at lowes. Not a bad investment if it works.
 
I have 32 feet of Class A double wall on an Englander 30. Even when I shut down the primary air, I hardly get secondaries because it is all being sucked so fast out of the firebox. With the primary shut down, there starts to be little torches of sir coming up from the ash pan port. I have reseated that thing and it is as snug as it will get(the ash pan trap door). I realize that a damper is not recommended by the manufacturer, but I would like to keep my draft down slightly so I can see my EPA stove actually work effectively.
 
fran35-I think you will be happy with one if you try it, cheap and you do not have to use it if it does not work out, I had scarey draft this morning with the secondaries being ripped around the baffle and the flue temp climbing like a tach on a 396 chevy.
 
i've used one for years on a variety of stoves. wouldn't be without one. adds more control to the draft and extends my burn time on my little Jotul F 3 CB. with a good bed of coals and some good wood, i don't need to coax it in the morning. helps shut it down if it gets too hot too. trick is getting it set in there right. i saw a @ a one foot piece of pipe with one already installed in it, the other day. where was that when i needed it. i put mine in a 3' section.

cass
 
fran35 said:
I have 32 feet of Class A double wall on an Englander 30. Even when I shut down the primary air, I hardly get secondaries because it is all being sucked so fast out of the firebox. With the primary shut down, there starts to be little torches of sir coming up from the ash pan port. I have reseated that thing and it is as snug as it will get(the ash pan trap door). I realize that a damper is not recommended by the manufacturer, but I would like to keep my draft down slightly so I can see my EPA stove actually work effectively.
I have 35' of class A and I am seeing secondary action I never saw before since adding a damper to the pipe. I use it everyday now and mostly completely shut. I'm wondering if mfg recommendations are based on the typical chimney some of us don't have.
 
wkpoor said:
fran35 said:
I have 32 feet of Class A double wall on an Englander 30. Even when I shut down the primary air, I hardly get secondaries because it is all being sucked so fast out of the firebox. With the primary shut down, there starts to be little torches of sir coming up from the ash pan port. I have reseated that thing and it is as snug as it will get(the ash pan trap door). I realize that a damper is not recommended by the manufacturer, but I would like to keep my draft down slightly so I can see my EPA stove actually work effectively.
I have 35' of class A and I am seeing secondary action I never saw before since adding a damper to the pipe. I use it everyday now and mostly completely shut. I'm wondering if mfg recommendations are based on the typical chimney some of us don't have.

This comes up from time to time-- http://www.gulland.ca/florida_bungalow_syndrome.htm
In short, yes, I think they test them with 15ft flues. So the use of a damper is entirely justified for those with excessive draft IMO.
 
Some stove makers set a maximum height chimney for their stove (ie: Avalon sets it at 33ft.). Others, like Jotul recommend a butterfly damper for excessive height. When the height exceeds the recommended height limit, a damper can be a reasonable solution to try.
 
Where might a damper be installed if the outlet goes straight out the back of the stove into a liner?
 
Jim Buckhorn said:
Where might a damper be installed if the outlet goes straight out the back of the stove into a liner?
There is no single- or double-walled stovepipe between the flue outlet and the liner?

In that event you can't install one unless the flue collar has holes to accommodate one. If you having an overdraft situation with an EPA certified stove it may be worth finding a way to narrow/restrict the intake air source.
 
Thanks!

Here's what happened over here. The first burns in our stove went fine, but around the third burn the house filled with smoke. The screw clamp wasn't tight on the rain cap and it dropped down--no smoke out the chimney, all smoke into the house. But I noticed that since then I've never had a stove temperature higher than 450*. I thought I might try a damper. There is single-wall piping between the stove and the flue snout, and it looks like a key damper would be installed in between. Many thanks for the video, woodmiser.
 
You are welcome.

Happy New Year
 
spirilis said:
wkpoor said:
fran35 said:
I have 32 feet of Class A double wall on an Englander 30. Even when I shut down the primary air, I hardly get secondaries because it is all being sucked so fast out of the firebox. With the primary shut down, there starts to be little torches of sir coming up from the ash pan port. I have reseated that thing and it is as snug as it will get(the ash pan trap door). I realize that a damper is not recommended by the manufacturer, but I would like to keep my draft down slightly so I can see my EPA stove actually work effectively.
I have 35' of class A and I am seeing secondary action I never saw before since adding a damper to the pipe. I use it everyday now and mostly completely shut. I'm wondering if mfg recommendations are based on the typical chimney some of us don't have.

This comes up from time to time-- http://www.gulland.ca/florida_bungalow_syndrome.htm
In short, yes, I think they test them with 15ft flues. So the use of a damper is entirely justified for those with excessive draft IMO.

Excellent article you linked to there by John Gulland. I've read quite a bit by him but hadn't seen this article. Good info for any that haven't read it. Thanks
 
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