About those flue dampers.

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WS - I agree 100% with your first post.
I have a PE Spectrum with a 25 ft stack. It overfired regularly until I modified(bent) the damper stop tab. Works great now.
I bet if I had a 10 ft chimney this stove would be fine in stock mode. There is not a one size fits all program for this.
I tried modifying the control on mine... modified the linkage, bent tabs, separated the primary and secondary controls, blocked off holes, drilled new holes, tried a grate, and I-don't remember-what-all. I could make it better... not great... but then the weather would change and...
Now the thing is in my garage/shop with a 16 foot chimney running straight up through the roof (installed exactly to the manual)... I've re-done and un-done all the same stuff... I'm still not impressed. I get the best performance by settin' the key damper just barely open enough so smoke/flame won't spill out the door when it comes up to temperature... "best" performance, not great performance. But that's me and mine... not you and yours.
My biggest complaint is the waste... dead, black, unburnt charcoal in the bottom unless I babysit the damn thing. I literally have to stir 'n' rake the coal bed every 10 minutes or so to get any heat from the coal bed... and if I don't stir 'n' rake the coals just die out. I can't (and don't wanna') be babysittin' it like that... so if fills with those dead and dieing coals... and I end up tossin' out somethin' like ¼, or more, of the fuel I put in the thing. Of course, if it burned on a grate system, with combustion air fed under the coal bed (rather than over it), it would be a non issue... but that ain't happenin' without guttin' 'n' rebuildin' the thing.
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I tried modifying the control on mine... modified the linkage, bent tabs, separated the primary and secondary controls, blocked off holes, drilled new holes, tried a grate, and I-don't remember-what-all. I could make it better... not great... but then the weather would change and...
Now the thing is in my garage/shop with a 16 foot chimney running straight up through the roof (installed exactly to the manual)... I've re-done and un-done all the same stuff... I'm still not impressed. I get the best performance by settin' the key damper just barely open enough so smoke/flame won't spill out the door when it comes up to temperature... "best" performance, not great performance. But that's me and mine... not you and yours.
My biggest complaint is the waste... dead, black, unburnt charcoal in the bottom unless I babysit the damn thing. I literally have to stir 'n' rake the coal bed every 10 minutes or so to get any heat from the coal bed... and if I don't stir 'n' rake the coals just die out. I can't (and don't wanna') be babysittin' it like that... so if fills with those dead and dieing coals... and I end up tossin' out somethin' like ¼, or more, of the fuel I put in the thing. Of course, if it burned on a grate system, with combustion air fed under the coal bed (rather than over it), it would be a non issue... but that ain't happenin' without guttin' 'n' rebuildin' the thing.
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Well WS I'm new to these Epa stoves... I burnt wood in a home build wood furnace for 25 or 30 years...I paid 90.00 dollars for it.....The guy who built it did a nice job..... Now the winter of 2013/2014 I burned between 4 and 5 cords through the old dragon....This past winter I installed a Heatmax,..... Now I didn't follow the factory recommendations right to a tee...I had a perfectly fine masonry clay lined chimney.."inside dimensions of the clay liner was 6.75 x 6.75...... So I plugged her in after a few weeks it became apparent I needed to install a BD which I did...

Now after doing that and setting it to the recommended water column settings.... I started to notice high temps on the front of the unit when it went into secondary burn and there seemed to be no stopping it really....Obviously there is always a way .....Open the BD full for one also open the clean out door on the chimney .... basically kill the draft..... I also make a couple plates that I could use to block of the secondary air inlets..... I've been running the heatmax with about half the secondary air and most days I crack the primary damper open with a paperclip about an 1/8 " that seems to work the best for me ....

Man I was constantly messing with the BD , coaling problems especially when it was cold say below 10 degrees which happens a lot here in Maine.....I was constantly baby setting the thing to get the coals burnt down while the house would go cold .... I'm am not a fan of this cycle burning bull... I had to tell the wife not to throw wood in it would screw the whole process up.. I burned just as much wood through the thing "5 cords" and was no where near as warm as I was with the old furnace....

Bottom line is "like you say" everybody system in different its not one shoe fits all .....so many things affect draft and the lack there of...... inflexibility with some of these Epa stoves are causing a lot of headaches for people .... Obviously burning wood is not just a do it thing common sense alone experience you learn the do's and don't needed to burn safely ....

I"m in the process of hooking up FC 700E called the factory about Baro verus in line key damper....Tec said we do not recommend Baro... use an in line cast damper...... hope I didn't derail
 
however I do agree that there are stoves out there that can have the air shut to the point of starving the fire...mine being one of them, I can shut it down so far that it smokes like a damn steam engine...I believe the operators manual would "make up" for the air adjustments, as it likely tells the operator how to adjust the settings to be EPA compliant? im just guessing though

This is true on my stove. I can choke the fire out with the 2 controls that are on the front of the stove. No need for a flue damper on mine.
 
This is true on my stove. I can choke the fire out with the 2 controls that are on the front of the stove.
OK... I believe ya' (what kind/vintage of stove??).
But I just gotta' ask... if ya' ain't never tried one (with the current set-up), how can ya' possibly know a flue damper wouldn't make an improvement in performance??
I mean... seriously... how can ya' possibly know??
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OK... I believe ya' (what kind/vintage of stove??).
But I just gotta' ask... if ya' ain't never tried one (with the current set-up), how can ya' possibly know a flue damper wouldn't make an improvement in performance??
I mean... seriously... how can ya' possibly know??
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Just a guess, but if it's 100% dampened off with the controls built into the stove I don't believe a damper would make a difference....unless it could get me to 110% ?
 
Well greenskeeper, I posted this in another thread recently.
It's something I've actually done... have you??

Just because something works a certain way on paper don't mean it will work that way in actual practice... and that's been proven time 'n' time again.
Tell ya' what ya' do.

  1. Get a good fire goin' in your stove, then slowly start closin' the air inlet and watch how the fire reacts.
  2. Do the same thing with the flue damper and watch how the fire reacts.
  3. Get the fire goin' good again, leave the flue damper open and close the air inlet to minimum for ½ an hour... measure the temperature of the stove top and sides.
  4. Do the same thing but leave the air inlet open and close the flue damper to minimum for ½ an hour... measure the temperature of the stove top and sides.
  5. Try it with the flue damper open ¾ and the air inlet closed ¾... measure the temperature of the stove top and sides.
  6. Again with the flue damper closed ¾ and the air inlet open ¾... measure the temperature of the stove top and sides.
  7. Come back and tell me, with a straight face, they do the same exact thing and it don't make any difference which one you use to adjust the stove.
 
Well greenskeeper, I posted this in another thread recently.
It's something I've actually done... have you??

Just because something works a certain way on paper don't mean it will work that way in actual practice... and that's been proven time 'n' time again.
Tell ya' what ya' do.

  1. Get a good fire goin' in your stove, then slowly start closin' the air inlet and watch how the fire reacts.
  2. Do the same thing with the flue damper and watch how the fire reacts.
  3. Get the fire goin' good again, leave the flue damper open and close the air inlet to minimum for ½ an hour... measure the temperature of the stove top and sides.
  4. Do the same thing but leave the air inlet open and close the flue damper to minimum for ½ an hour... measure the temperature of the stove top and sides.
  5. Try it with the flue damper open ¾ and the air inlet closed ¾... measure the temperature of the stove top and sides.
  6. Again with the flue damper closed ¾ and the air inlet open ¾... measure the temperature of the stove top and sides.
  7. Come back and tell me, with a straight face, they do the same exact thing and it don't make any difference which one you use to adjust the stove.
:clap::clap::D
 
Olyman - You need to find the "kneel-n-bob" emoticon, it would be more appropriate.
and we need to find you a false baby nipple,,as thats about all your good for. your second behind slowp for troll,,might want to try harder, loser..to bad all your good for is a troll...must be a worthless drug filled life...
 
In the 4 EPA wood heating units I've owned I have never needed a damper of any kind . They always worked great on their own . However My chimney is not over 18 feet high so that probably plays a big role . Every non EPA unit I've had I used a key damper in the flue to try to keep the heat in the unit and more so on windy days. A flue pipe is like a vaccum cleaner the higher the draft ( taller chimney) the more suck you get . Sometimes you gotta do what you gotta do to keep that in check. I could see how a guy with a 25+ foot chimney needs a damper of some kind regardless if it's EPA or not
 
A flue pipe is like a vaccum cleaner the higher the draft ( taller chimney) the more suck you get . Sometimes you gotta do what you gotta do to keep that in check. I could see how a guy with a 25+ foot chimney needs a damper of some kind regardless if it's EPA or not

I could too, and that's a reasonable way of thinking about it. If I were in that spot where I was unsure, I'd measure the draft. Search the bay for Dwyer Manometer- there's a pile of them for less than fifty bucks. For fifty bucks, you'd know if your draft was correct, you'd be able to adjust a barometric damper if you installed one, you'd be able to impress your kids with a tube and a little red fluid.
 
...you'd be able to impress your kids with a tube and a little red fluid.
:laughing:
The only way you're gonna' impress my two oldest is if it's done with a smart phone app.
The 7-year-old ain't impressed with anything that don't have an internal combustion engine, wheels, and makes lots of noise.
A little red fluid in a tube would be about as interesting as boiled spinach.
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So @Whitespider I have a Question/challenge for you and your giant pulsating brain. My furnace has a BDR, a BDR regulates draft and opens to slow draft down. So the question to you is, why is it that upon startup and the ash drawer is open bringing in lots of air under the fire. Then the damper opens bringing more air in, in front of the fire, the BDR is closed. But when I shut the ash drawer stopping all that extra air the BDR opens, telling me I have more draft with less air.
 
...when I shut the ash drawer stopping all that extra air the BDR opens, telling me I have more draft with less air.
The draft (the amount of suck) ain't changin' when you close the ash drawer... the draft (amount of suck) remains the same.
With the ash drawer open the air flowing through the firebox and into the pipe is near the maximum the suck can pull.
When you close the ash drawer you reduce the amount of air flowing through the firebox, resulting in more of the total "vacuum" acting on the BDR, and less on the firebox.
You don't have "more" draft when you close the ash drawer, you've just redirected some of it to the BDR. The fact is, when you close the ash drawer and the BDR opens, there is less draft acting on the firebox, not more.

Both the BDR and a key damper reduce the draft (suck or vacuum) acting on the firebox, but neither can change the total draft being created by the chimney (other than the slight difference flue gas temperature would make by using either).
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Both the BDR and a key damper reduce the draft (suck or vacuum) acting on the firebox, but neither can change the total draft being created by the chimney (other than the slight difference flue gas temperature would make by using either).

I agree with this ^^^ except to say the BDR only reduces draft after draft has gone beyond the draft needed.

The draft (the amount of suck) ain't changin' when you close the ash drawer... the draft (amount of suck) remains the same

I agree with this part. ^^^

When you close the ash drawer you reduce the amount of air flowing through the firebox, resulting in more of the total "vacuum" acting on the BDR, and less on the firebox

I do not agree with this. ^^ The firebox is down stream from the BDR The BDR setpoint is what allows the maximum flow through the fire box, so when it is opening at that time the maximum draft is flowing through the firebox. If the ash drawer open is not opening the BDR then there has to be less draft.
 
The firebox is down stream from the BDR
I believe this is where your confusion lays... the firebox is upstream from the BDR, not downstream.
If you're swimin' against the current you're swimin' upstream... if you could swim from the BDR to the firebox, you'd be swimin' against the current (or upstream).
If you widen the river the current slows down, if you narrow it the current speeds up... in either case the same amount of water flows past you every minute as you stand on the bank. But, if the water is flowing past you left-to-right, and a second river dumps into the first on your right side (the BDR), there will be both faster current and more water flowin' per minute downstream (in the chimney) from where you stand (at the firebox).

Now if you open the ash drawer it's like the second river dumpin' into the first on your left, rather than your right... and that increases both the current speed and water volume flowing past you.
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i got a atmospheric damper in my stove pipe i keep the inlet in my stove almost closed
when i got a good fire in it.
 

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