To Add A Damper or Not?

[soupy1957]

oldspark: nope.........not "half way" issues.........only "full closed" issues. As I said, it's probably just a learning curve thing and I'll revisit the place where I bought the stove, before the burning season gets under way, and walk thru the basics again. It may indeed be, that adding a damper on the flue is not going to help, so I'm not gonna run out and get one. Just learning more and more about the ins and outs of burning inside a closed system.

-Soupy1957

 

[oldspark]

As some one else stated the stove manufactors say not to use them period, a couple of exceptions would be for a too strong a draft and you do not have that problem.
This link talks about putting dampers in because of too much draft but gives you an idea of how they affect the chimney and stove.
http://www.chimneysweeponline.com/hoxdraft.htm

 

[Todd]

How was your wood last year? These EPA stoves can be fussy if your wood isn't dry enough.

 

[firefighterjake]

This thread was written because of the fact that I hadn't yet really gotten a handle on why it is that when I close down my airflow control on my stove, it seems to nearly kill my fire altogether. Sure.........the air is being cut back and without air, a fire won't burn ...........but I thought the dampers on the new stoves were supposed to STILL allow SOME airflow.

It's just a learning curve thing. I had plenty of chances last season to get a feel for the system we own, and I DID often put the damper 1/2 way closed after the initial fire got settled in. I'll master it sooner or later. Just thought that perhaps the damper that you can get for the flue pipe, would perhaps be a bit more manageable.

I have seen the airflow diagrams that Avalon puts out there for public consumption, but I have YET to see any actual breakdown of the damper itself; how it sits in the stove, what it is.........etc.. Someone in here put an image at one point, of the design, but it was not clear what I was looking at. Since I will not be tearing my stove apart (perhaps in 30 years I may) to see how it is constructed, I'll have to try and visualize it somehow.

It's enough to say, that I get too much "shut down" with the air control fully "forward" (closed) and I thought I might be able to have more (better) control, with a damper in the flue.

-Soupy1957

Typically when someone closes down the air and the fire nearly goes out it usually due to the fact that the fire is not getting enough oxygen . . . yes the air controls in EPA stoves do not allow the stove to be air-tight, but just like us fire likes a certain amount of oxygen . . . best analogy my dense firefighter brain can come up with is being asked to run a 100 yard dash . . . with only a straw in your mouth and not being able to take in oxygen through your nasal passages . . . yeah, it can be done . . . but it's a tough go . . . and while technically you still are getting oxygen you are not getting enough to get the job done efficiently.

The object to achieve secondary combustion in a stove is to get the stove hot . . . and then once the fire is going (and this is where you may find the probe thermometer to be a real asset since I wait until the temps are running in the green) . . . you start to slowly dial back the air . . . depending on your set-up and the all-important how seasoned your wood is factor you may be able to shut the air all the way "closed" (although it is still open a bit), a quarter way or you may have to open it up again if the wood is less than optimal or if the temps are not good.

Getting the fire going is often the easy part . . . keeping it going while shutting the air control can be a bit more of challenge sometimes . . . and getting a sustained secondary burn can be even more of a challenge. To reiterate . . . it all starts with seasoned wood . . . but then you need to get the temps up and then slowly back things down with the air . . . which takes me 15-30 minutes before the stove is cruising along nicely with good secondaries from a cold start.

A damper would do nothing for you for the problem you mention . . . if you had a problem with fires going way too hot even with the air control shut all the way and had a tall chimney than I might suggest a damper, but like another poster to me a damper is a relic from the past and offers very little advantages for the modern wood burner.

 

[soupy1957]

Todd: wood was "seasoned" yes.

FirefighterJake: You said "Getting the fire going is often the easy part . . . keeping it going while shutting the air control can be a bit more of challenge sometimes . . . and getting a sustained secondary burn can be even more of a challenge. To reiterate . . . it all starts with seasoned wood . . . but then you need to get the temps up and then slowly back things down with the air . . . which takes me 15-30 minutes before the stove is cruising along nicely with good secondaries from a cold start."

That's exactly what I did last season, and it worked for me..........just noted that I never got it fully closed without risking a smoldering fire, is all. I reduced the opening about an inch or so, and let it burn a bit, then another inch or so, etc. etc..

-Soupy1957

 

[Todd]

Todd: wood was "seasoned" yes.

Is that what the firewood dealer told you? Seasoned can mean cut down a year ago and split the day before they deliver to your house and it doesn't mean it's dry enough. These stoves need firewood that is split and stacked for at least a full year or more for best results.

 

[ddown]

I have a thity foot Chimney and I need a pipe damper on extremely cold nights and not very much but it does help. The air pressure and draft do vary the longer you burn the more you get tuned into your draft.

 

[stoveguy2esw]

Todd: wood was "seasoned" yes.

FirefighterJake: You said "Getting the fire going is often the easy part . . . keeping it going while shutting the air control can be a bit more of challenge sometimes . . . and getting a sustained secondary burn can be even more of a challenge. To reiterate . . . it all starts with seasoned wood . . . but then you need to get the temps up and then slowly back things down with the air . . . which takes me 15-30 minutes before the stove is cruising along nicely with good secondaries from a cold start."

That's exactly what I did last season, and it worked for me..........just noted that I never got it fully closed without risking a smoldering fire, is all. I reduced the opening about an inch or so, and let it burn a bit, then another inch or so, etc. etc..

-Soupy1957

the thing to understand is every chimney/house is different you could have two chimneys in what looks to be identical houses next door to each other and have different nuances to the flue's performance. many factors are involved not just flue height and 10/3/2 rule compliance. im not gonna get deep into it but here's my take on your situation. while a 15 ft flue at the proper height in relation to the roof is generally what stoves are designed to operate at (as a minimum flue height from the floor of the firebox) flue diameter and possible air intrusion may be hurting you or possible negative pressure. a few simple things to check:
1. are your connector pipe joints sealed gas tight?
2. does your flue have a "clean out door" if so does it seal gas tight (you would be amazed at the effect a leaking ash door can have on draft)
3. what is your flue diameter? modern units should be connected to a flue no more than 2X the square inches of the flue opening on the stove (6" is 28.8 sq. in.) a large flue may not be able to hold enough heat to maintain the stack velocity needed to pull a phase 2 stove to optimal.
4.does opening a window in close proximity to the stove affect your fire (would take about 10 minutes to see a difference if it does, not an immediate change. if so an OAK may be the solution.

hope this helps ya

oh and BTW, IMHO do not install a damper in the flue connector pipe , you do not need it

 

[overnight burn]

the right answer to that question is that these new stoves do not require dampers. THey are designed to run with out one.If youdo install one it will burn completely different than it's designed to (secondary burn, air wash) also the rod that lets the air in is called a draft control rod, not a damper.

 

[vvvv]

Does that mean no more MagicHeat draft reducer?

Once the wood has burned, i want any leftover exhaust to quickly exit, hopefully cleanly.
pyrolysis? I dont think u understand phases of wood burning
first sentence was copied & pasted, second is response. MH on EPA stove results will soon be available from VCBurner

 

[Todd]

the right answer to that question is that these new stoves do not require dampers. THey are designed to run with out one.If youdo install one it will burn completely different than it's designed to (secondary burn, air wash) also the rod that lets the air in is called a draft control rod, not a damper.

They are also designed to run with a 14-16' chimney, so what do you do if you have twice that height? Just let it over fire?

 

[Todd]

Does that mean no more MagicHeat draft reducer?

Once the wood has burned, i want any leftover exhaust to quickly exit, hopefully cleanly.
pyrolysis? I dont think u understand phases of wood burning
first sentence was copied & pasted, second is response. MH on EPA stove results will soon be available from VCBurner

I can tell you the results I had with a MH on my old EPA stove = more creosote

 

[vvvv]

Does that mean no more MagicHeat draft reducer?

Once the wood has burned, i want any leftover exhaust to quickly exit, hopefully cleanly.
pyrolysis? I dont think u understand phases of wood burning
first sentence was copied & pasted, second is response. MH on EPA stove results will soon be available from VCBurner

I can tell you the results I had with a MH on my old EPA stove = more creosote

OK
what kind of creosote & where did it deposit? how much more?
how meticulous were u about the MC content of the wood?
i realize that the unextracted heat/energy can better expel uncombusted particulates into the air but also hate to clean a chimni & get minimal creosote out of it which i'd reburn anyway. i do know that if a stove has a propensity to overfire, a MH will help control it automatically

 

[Todd]

Does that mean no more MagicHeat draft reducer?

Once the wood has burned, i want any leftover exhaust to quickly exit, hopefully cleanly.
pyrolysis? I dont think u understand phases of wood burning
first sentence was copied & pasted, second is response. MH on EPA stove results will soon be available from VCBurner

I can tell you the results I had with a MH on my old EPA stove = more creosote

OK
what kind of creosote & where did it deposit? how much more?
how meticulous were u about the MC content of the wood?
i realize that the unextracted heat/energy can better expel uncombusted particulates into the air but also hate to clean a chimni & get minimal creosote out of it which i'd reburn anyway. i do know that if a stove has a propensity to overfire, a MH will help control it automatically

This was back in 1997 with a Energy King Legacy non cat. Creosote was worst at top of chimney but I also had it lower. The firewood was mostly Hard Maple and Birch split and stacked in early Spring and burned that following Winter. Probably wasn't the best wood but after I ditched the MH the chimney was much better.

I had a friend with an old pot belly stove who used a MH and it worked fine for him so I thought I'd try the same. I guess the pot belly had much higher flue gas temps to spare verses my EPA stove. I even tried ducting off the front of the MH into my furnace duct above the stove which gave some heat into the far upstairs bedrooms but I just had too much creo to my liking and got rid of it.