A better explanation...

[Whitespider]

Hey, for you guys advocating the baro damper I want you to think about this.
I already have two... sort'a.

The chimney is shared with two gas appliances, a furnace and a water heater. Gas appliances use a hooded exhaust... sort'a like an exhaust hood over a kitchen stove. Both are always wide open and sucking air. The 3-inch water heater pipe enters the chimney a few inches below where the wood stove enters it...basically a wide open 3-inch round opening sucking air all the time. The wood "stovace" has 2-feet of vertical 6-inch pipe into an 8-inch tee... one end of the tee runs horizontally 2-feet over to the chimney (so I have one section of vertical 6-inch pipe, and one section of horizontal 8-inch pipe, joined by the 8-inch tee). The other end of the tee has the 4-inch furnace pipe entering it... basically a wide open 4-inch round opening sucking air all the time.

Now before anyone starts pointing at that as the problem, go back and read the posts in this thread... I blocked off the gas appliance openings on two different 30-36 hour tests, and it didn't help one single bit. There was absolutely no noticeable difference at all... in fact, it might have been worse, but how would you know for sure?

Now I'm not claiming a baro won't work... ain't no way to know for sure without a test.
And like I said, the time for testing is past.

Just something I wanted y'all to think about when recommending the barometric damper.
I'm already bleeding a lot of draft from the wood stove... and it's still excessive in arctic temps.

 

[Whitespider]

2. They cool of your chimney too much so you lose draft and/or make creosote. If the chimney cools off too much, your draft drops and the BDR door closes maintaining the draft. ...all the fresh air mixing in dilutes the smoke. ...after the BDR is pretty cool, but I have great draft and the chimney has some soot, but very little cresote.

Heck, I'm believing ya'...
My set-up has two always-open openings and I've never had any creosote problem... just a fine coating of soot that will wipe right off with your finger. I've actually thought that the fresh air is what must be keeping it so clean... but had (or have) no way to verify it.

 

[stihly dan]

Spidey, I meant for the new daka, I fully understand the wood stove is over. I was just recommending it for the daka, so that there would be an exact even set draft thru it. May make it easier to run, or run better. Also not making a statement, you would know better. But when your running an appliance isn't the draft focused on that particular appliance, path of least resistance. Rather than pulling thru all appliances. I don't think either way would be wrong, but for $20 why not? Just my 2 cent's. You know I'm you side with this buddy.

 

[Whitespider]

I almost forgot...
At one time the chimney had a fourth appliance connected to it, a wood-fired cook stove in the kitchen.
There was never any weak draft problems of any sort and Ive never cleaned the chimney in... well, the wife tells me it will be 21 years in August since we moved in. I inspect it every year... nothing but a fine layer of soot. I open the clean-out next to the floor in the basement every year... usually find about a cup or so of fine soot laying there. And guess what? I don't even need to clean that out... I just stir it up a little and it gets sucked out the chimney.

Heck, maybe it stays so clean because there's a coating of oil on it... when we first came here the old monster coal furnace had been converted to an oil furnace. That had to be the most inefficient thing I've ever used... it sucked up fuel like a pullin' tractor in the money round.

 

[Whitespider]

stihly dan,
$20 for a baro damper? Tell me where. The ones I see are normally around $100... but for $20 I'd put one in inventory just in case!

 

[stihly dan]

I picked one up at lowes before I realized one came with the kuuma.

I have a 6 in one I could send ya for free.

 

[brenndatomu]

I picked one up at lowes before I realized one came with the kuuma.

I have a 6 in one I could send ya for free.

Nice Dan. Good guy BDR rep incoming!

I was just gonna say someone has a new Fields 6" on fleabay right now for $11.50

 

[Whitespider]

Well that's darn nice of ya' to offer me the free baro... but I'm not gonna' put one on the current stove anyway.
I'll shop around and research it a bit for the DAKA... but if they can be had for that little it would cost darn near as much to ship it as I should be able to buy it. Hang on to yours for now, maybe someone local can use it... but don't think I'm unappreciative, I just feel like I'd be taking advantage on something like that.

 

[Oxford]

If the new stove really calls out 0.06 iwc draft as posted, better start thinking now, because assuming a 40' chimney height, 0F outdoor temperature and a 450F stack, the natural draft calculates as .32 iwc, or about five times max. Which also explains your "coaling" issue. They're not coals, they're charcoal, made by incomplete combustion. Whether that incomplete combustion is due to a layer of ash, lack of oxygen, or, my bet, the simple physics that make a match blow out on a windy day, no matter. Also, I would strongly consider a fresh air makeup isolated as much as possible from the rest of the home, since that draft will pull 700+ cfm of air through a 6" opening. That's equivalent to 2 tons of air conditioning at 55 F outdoor air and substantially more at lower temperatures.

I would put a manometer on that stack now, so that I could plan for my next install. I suspect you won't, because your giant pulsating brain doesn't require any actual data, just good ol common sense. Next winter, when the new stove you got from a member here isn't working the way you want, I hope that same common sense prevents you from running your mouth about that stove and by extension, that member.

 

[Whitespider]

Wow Oxford,
Even though that post was slingin' mean at me... I sure liked it.
Your numbers tend to put it all in perspective... even my "giant pulsating brain" hadn't gotten around to doing the math :msp_thumbup:

 

[Whitespider]

Ummm... One more thing Oxford (serious question),
The next time someone tries to tell me i have a weak draft problem, do I have your permission to use your numbers in rebuttal? It sure would be a lot more handy and convincing than what have been doing.

Why didn't I think of running the numbers?

 

[stihly dan]

Just went down to give the furnace it's good night dinner. As I was pulling the ashes down the grate, I realized I am glad it does not have glass. I thought that was the one thing I wish it had. But if it did it would most likely have had an air wash system. Instead of the primary air blowing right along the floor burning all the coals. Luckily kuuma cares more for performance than luxuries. Or I may have had the same problem as the stove.

 

[Steve NW WI]

Just went down to give the furnace it's good night dinner. As I was pulling the ashes down the grate, I realized I am glad it does not have glass. I thought that was the one thing I wish it had. But if it did it would most likely have had an air wash system. Instead of the primary air blowing right along the floor burning all the coals. Luckily kuuma cares more for performance than luxuries. Or I may have had the same problem as the stove.

I'm a glass convert - call me a fire watcher or what you want, but it's neat to see how things are going whenever you want. Between posts today in this thread, I actually spent some quality time on the floor with the dog just watching the secondaries do their thing. Best thing on "fire TV" short of a good brushpile at full burn. Watching fire helps clear the mind.

Anywho...the primary/airwash air in my unit does a good job of keeping the glass clean, and I beleive (judging by the burn pattern when it's winding down) that it's responsible for burning down much of the coals. Whether it's efficient or not is up to debate by people with more expertise than me.

This thread had me thinkin tonight at work - I think I have an idea that would solve Spidey and others' coaling problems. It'd need to be designed into the stove though, or require cutting and welding on an existing stove. Maybe, just maybe, I'll have to build a half scale stove with my idea built in just to see if it will work. Side benefit: Wood heat for the ice shack. Not gonna say much more, as IF (and IF is the biggest two letter word out there, I know) it didn't adversely affect emissions performance, it might have commercial value.

 

[Whitespider]

I’ve sort’a learned-to-like the glass door thing also. Not so much that I like to sit and watch the fire (although I have done that), but it sure is handy for a quick check of the fire. Just before I bought the used DAKA I was looking at the Englander furnace. They have a glass door and air wash, but also have a grate system and a separate spin draft located under it… I was thinking maybe that would be the “best of both worlds” type of thing. I’m not so sure it’s fair to say stove makers using glass doors and air wash systems care more about luxuries than performance… keep in mind that furnaces, such as Kuuma, are legally exempt from EPA certification(even if they claim to pass EPA tests).

One reason (as I see it anyway) for the glass, is to allow lots of radiant heat to escape from the firebox. Out of necessity, the new EPA stoves try to keep firebox temps high, which improves combustion efficiency, which helps to pass the tests. Those high temps require some amount of protection of the steel, so most are lined with refractory materials (i.e. firebrick)… which not only protects the integrity of the steel, it aids in keeping combustion temps high. But refractory brick is an insulator of sorts, it will slow the rate of heat transfer to the steel, and therefore from the steel to the space and air around it… the glass door makes up for this rate loss in spades when the stove is used as a space heater (as it is intended to be used). Radiant heat is what makes the “body” feel warm, air conduction/convection heat not so much. Think about stepping out of a lake after a swim on a hot summer day… even when its 90[sup]o[/sup], if it’s cloudy any breeze will feel cool to the body, but if the sun is shining (radiant heat) it will near instantly feel hot to the body, and will overpower the “cooling” effect of most any “normal” breeze.

I no longer blame the stove for my problems, or its design by the manufacturer… after all, they have done exactly what they are required to do under EPA regulations. Besides, it ain’t like Pacific Energy didn’t warn me in their manual (although no draft numbers in the manual)…
“The chimney flue size should be the same as the stove outlet for optimal performance. Reducing or increasing the flue size may adversely affect stove performance.”
But I do see the EPA requirements, and therefore the resulting design, as a contributor to the problems I’m having… under my installation conditions (which are not condoned be the manufacturer). Whether-or-not the EPA requirements are a good thing, or a bad thing, or need revising, or whatever doesn’t change what-is-what-it-is. Using the old air-tight design, with a single air intake under a grate (thereby forcing the air to be pulled up through the fire) and a single combustion gas exit, I was able to close the draft control and/or flue damper to the point it would run properly… and I thought I could do the same with an EPA design. Well, I was flat wrong (there, I said it)… and that’s all on me. Trying to place blame somewhere else is simply being pig-headed and refusing to take responsibility for my own mistakes… I didn’t do the study and research I should have, plain and simple.

And while I’m in the mood to admit my part in this fiasco…
No doubt, if connected to a recommended chimney, pulling draft somewhere within specification, my “stovace” would have performed as I expected/wanted… or at least close. There have been dozens of things posted, pointing to what the problem is… such as my modifications, poor draft, blower, and so on. There was one thing posted by Del I believe (man I hate to admit that)… simply… “A Bad Install.”

Well... that pretty much sums it up… don’t ya’ think?

 

[Whitespider]

Just to keep on the “informational” theme of this thread…
This morning the temps (and my draft) are sort’a in the intermediate stage… 10[sup]o[/sup] but no wind to speak of. The “stovace” is running almost exactly like the article I linked to describes. When I got up at 4:00 it was a bit cool in here (67[sup]o[/sup]) so I filled the box with oak… now, just 2½ hours later the oak is nearly consumed (short burn time), and although there is a coal bed it ain’t really what I’d call excessive and is burning and heating to some degree (stove steel way to hot to touch). Still, probably an hour or so from now I’ll need to reload (less than a 4-hour burn time)… but if it was a bit colder, or the wind was blowing, I’d have a monster bed of (almost) non-burning coals and be needing to reload now (and the stove steel would be cool enough to sit on).

Just some FYI.

Oh... and if it stayed at 10[sup]o[/sup] all day, the deep, none-burning coal bed would eventually manifest itself. It's just in extreme cold or wind, that it appears on the first load, or would have already been present when I got up this morning. If it was around 0[sup]o[/sup] and blowing, I would have needed to shovel out the coals (charcoal) to make room for the daily burning.

 

[stihl sawing]

Just to keep on the “informational” theme of this thread…
This morning the temps (and my draft) are sort’a in the intermediate stage… 10[sup]o[/sup] but no wind to speak of. The “stovace” is running almost exactly like the article I linked to describes. When I got up at 4:00 it was a bit cool in here (67[sup]o[/sup]) so I filled the box with oak… now, just 2½ hours later the oak is nearly consumed (short burn time), and although there is a coal bed it ain’t really what I’d call excessive and is burning and heating to some degree (stove steel way to hot to touch). Still, probably an hour or so from now I’ll need to reload (less than a 4-hour burn time)… but if it was a bit colder, or the wind was blowing, I’d have a monster bed of (almost) non-burning coals and be needing to reload now (and the stove steel would be cool enough to sit on).

Just some FYI.

Wow, only three to four hours. You do have something wrong there. I wouldn't think a bad setup would cause it to burn that fast unless the air vents are wide open. Mine will do that but you can't run them open cause the stove will overheat. Now the oak i'm burning now is pretty old so it's burning fast but not like yours. Hope you get it figured out, that would aggravating getting up every three hours to fill a stove. Almost make you want to turn the thermostate on the wall up if you have other heat.

 

[Whitespider]

OK… now we’re at the 3-hour mark and it begins.
I could tell it had stopped heating by the air coming from the heat vents. Went down and laid my hand on the bare steel, it was hot, but not so hot I couldn’t leave my hand there... more like real warm. Pretty decent size coal bed… enough to fill a 3-gallon bucket anyway. I raked the coals into a pile right in front of the door (right in front of the “boost” air holes) and opened the draft control and flue damper completely. That will gain me around 20 minutes to maybe a half hour of some moderate heat, and burn down the coals some. I’ll be reloading at 7:30 I’m sure… just 3½ hours from start-up… and the coal bed will start to accumulate until the temps outside increase. It’s really weird, at about 25[sup]o[/sup] or so (depending on wind) the coal bed will magically make the stove steel screamin’ hot again, and just burn up. But if it stays cold… they’ll just stall-out and eventually die.

Now it’s almost become a funny joke… makes me laugh (I’m not sure what I’m laughing at though).
When it's down-right arctic out, I'd have already reloaded well over an hour ago.

 

[Oxford]

It's not weird at all. Until the difference in temperatures between your stack and the outdoor temperature comes correct, the draft is not in a range that allows your stove to properly circulate combustion air, flammable gasses, and combustion products and approach ideal combustion. A manometer on the stack would tell you that.

You keep saying you know it's all on you, and then you post things that imply it's really still the stove. You're welcome to use the numbers I posted earlier, but remember that they show that while you don't have a weak draft problem, you pretty clearly have an overdraft, which is also, say it with me, a draft problem. I get that you don't want to resolve it, that you instead plan to overturn the laws of physics on appeal, but resolving your draft issue would make your life easier IMO.

I know you plan on spending no time on this, but if you put a tee in the stack off your stove with the bullhead open to your basement and installed the flue damper in the bullhead, you could play with that damper and watch your stove come to life, I think. If I were you, I would install such a tee and cap it if nothing else when you install your next stove. You might be glad you did when it came time to install the barometric damper.

 

[brenndatomu]

Regarding having glass for viewing, it drives me nuts not being able to check the fire without opening the door! When I started heating with wood I used a stove that had a small rotating air control that you could peek through to see the fire. Then, when I installed the Big Jack, nothing. So I stole a design from one of our boilers at work, a small glass viewing port. Cheap, easy, effective. Just a 2.5" long 1-1/2" pipe nipple, a 1-1/2" pipe coupler, a round piece of high temp glass cut to fit inside the pipe coupler, and a small piece of gasket material. I cut a hole in the center of the furnace door with a hole saw, welded the nipple in leaving a inch sticking out, cutting the excess off the inside. Then I threaded the coupler on the outside and carefully "dropped" the glass into the coupler so it seats against the end of the nipple. I made a "nut" to hold the glass in by cutting off 1/4"-3/8" of the previously removed inside threaded end of the pipe nipple, cut some notches in it so a screw driver can be used to install/remove it. That gets threaded down into the coupler against the glass. I did isolate the glass from touching any metal by cutting some thin "washers" from the gasket material, 1 on each side of the glass. Don't overtighten the nut (buy spare glass untill you know what overtighten means ) Once it was assembled, I cut the excess length from outside end of the pipe coupler, so it was flush with the "nut"

I thought the glass would stay clean because it was back in a dead air space. Nope. :bang: Time to make an airwash system. I drilled 8 .125" (or 1/8") holes in the pipe coupler so that they are right at the inside edge of the glass.
I did the same on my current Yukon too, it works well. If I stack wood right up against the inside of the port, it will still smoke up the glass a little bit, but it takes 2 minutes to pull the glass out, clean and re-install. I think I have had to clean it twice this winter.
Anyways, it's a good compromise between a glass and a solid steel door. All due paying AS members are welcome to steal this idea...

 

[Whitespider]

7:35 AM – stove steel has turned cold – 4, maybe 5 inches of coals in the stove – reloaded.

Ya’ know what’s really sick? It’s supposed to get up over 30[sup]o[/sup] today… at some point after lunch that coal bed will magically come alive and start burning , the stove will get hot enough there won’t be any way possible to put your hand on the steel, and we’ll be opening the doors to let the heat out! But on the bright side… I won’t be shoveling it out and throwing it away like I was in January and February :msp_biggrin: