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Perhaps, but I have noticed that none of the linear thinkers are regularly complaining that their wood heated homes are uncomfortable.
Good stuff.

Regardless, it will be interesting to see how your experience with yet another stove turns out.
He got that Daka airtight job, we are waiting, I bet it works better.


I expect that it will give you ample opportunity to explain to those of us as yet unenlightened just how much smarter you are than the EPA and all those pointy-headed engineers with their soft hands and desk jobs.

Was that why they wear them pointy hats? Oh that was the Klan.
 
...you have to be willing to accept that sometimes you're wrong, that your intuition is incorrect.
I have no problem admitting that... my "intuition" that an EPA certified firebox would be better was in fact, way, way off base.

...your old stove heated better with less wood. ... Even if your contention is empirically true, it begs the question of why you changed it out...
Simple... the firebox cracked and the back wall warped after near 30 years of use. (not just a single year with different wood)

...it will give you ample opportunity to explain to those of us as yet unenlightened just how much smarter you are than the EPA and all those pointy-headed engineers with their soft hands and desk jobs.
One thing is more than certain... it ain't difficult to be "smarter" than a bunch of government pencil-pushers... and that there is just common sense!
 
Ok... now that I've had my nightly rest (and slept off the belly full of beer) let's get back to some rational discussion.

First of all the criticized flue set-up, with multiple appliances entering the brick chimney (which is the way it was done for well over a hundred years and works fine if done correctly). That was actually one of the easiest things to eliminate as the "cause". The two other appliances are the LP furnace and water heater... because the furnace isn't used (it's turned off and kept for back-up) I simply disconnected the 4-inch exhaust pipe and capped it. The 3-inch exhaust from the water heater took a little more thought... on two separate weekends I waited until morning baths were done and the heater had recovered, then shut down the pilot light and capped its chimney entrance. The tank held enough hot water for washing hands and a few dishes… and gave me about 30-36 hours of test session (mid-morning Saturday to mid-afternoon Sunday, on two separate weekends) before I had to fire it back up. During both test there was no noticeable difference, better or worse… it changed nothing at all.

stihly dan,
The multiple appliances entering the chimney makes it difficult to use a barometric damper… it can still be done as long as the appliance uses a relatively stable draft (such as an oil furnace) but won’t work properly on a wood fired appliance with varying draft during the firing cycle. The way my chimney is set up, my only option for draft control is a flue damper… and I wouldn’t have a wood-fired appliance without one (better to have it and not need it, than to need it and not have it).

Is the firebox too small for the application?? Maybe… maybe not… but that doesn’t explain why it won’t heat after the secondary burn shuts down and the fire collapses into a bed of coals, especially during frigid weather. The heat sensor that starts the blower is mounted in a vented metal box, which is mounted on the flue pipe about a foot above the firebox. There is plenty of heat in the flue, which keeps the blower running… if I touched the flue it would raise blisters, yet I can lay my hand on the bare metal parts on the front of the stove. Now it’s been suggested that the blower is cooling the firebox too much, and that was also simple to test… I just shut the blower off with a bed of coals in the firebox. Although the metal did get somewhat warmer, I could still lay my hand on it (and as a side note, yesterday during the warmer weather and light winds the metal was uncomfortably hot 14 hours after loading, with just a few coals in the box). I was actually impressed with the thing during the early part of the heating season, before it got really cold… it burned well and heated well. The metal plenum around it would be so hot you didn’t want to stand close for very long. But once the mercury dipped into single digits… well, you can sit on the plenum (after the secondary shuts down, which during extreme cold may only take an hour or less) and never break sweat. Being too small does not explain why the firebox is cold and the flue is hot… but what does explain it is that all the heat is exiting out the flue.

It’s also been mentioned that there might be something wrong with my box… like it’s broken, or was built incorrectly. Well… I got this from my brother’s father-in-law, who used it for a few years in his home before his wife put her foot down (she didn’t like the mess). He had it sitting on a raised hearth in the middle of his Family Room… which has a large opening at one end to the living room/dining room area, and another large opening at the other end into the kitchen. The kitchen and living room/dining room are separated by a half-counter (basically it’s just one big room). This stove would heat them right out of the house if he wasn’t careful how he loaded it, and it would heat all night long. When he gave it to me he told me just how wonderful it was, how well it worked, and how little wood it used. I’ve talked with him a length about my issues… he’s simply dumbfounded. But!! (and this is where I started researching the chimney height thing) His Family room has a flat roof, and with the stove sitting on a raised hearth he only had a total of 8-10 feet of chimney pipe on his installation… straight up and through the roof! The only real difference (that would affect how the thing burns, and hasn’t been eliminated as the cause) between the two installations is about 30 feet of chimney!

Now if you go back and read some of the threads and posts from December/January you’ll find a couple places where I express a belief that I was loosing too much heat out the chimney… which caused me to start using the flue damper. You will also find where I suspected that the secondary air was cooling the firebox and stealing heat after the secondary burn shut down. You will also find where I thought one of my modifications would be to disconnect the secondary air control from the primary air control so it could be adjusted independently (I ended up modifying the linkage so it doesn’t open as much, which helped a little… but it wasn’t a “fix”).

All the things I did, those mentioned here plus several others mentioned in other threads, improved performance… until the temperatures got a little colder. By the time temperatures fell below zero I was out of ideas. All the reasons some of y’all believe is the problem can only explain it partially, not completely… they don’t make sense when all the evidence and observations are applied (you’re not here on site, so don’t start again). There was just something strange going on and I couldn’t put my finger on it… until I came across that article, and it was like a light came on in my head. So far, the “Florida Bungalow Syndrome” is the only thing that explains all the symptoms, and explains why near all the things I’ve tried have made improvements… but only on a temporary basis, until temperatures dropped another notch.

See… I’ve heard everything that y’all have said. I’ve tested and eliminated those ideas as well as I could. I’ve considered that it could be a combination of problems… etc., etc., etc. But as I’ve worked with them and experimented, they just don’t make sense when all the evidence and observations are considered (this ain’t my first ride on the pony). Some of those observations are subtle… hard to explain… you’d have to have been there type things. Really, the only piece that fits in the last hole of this puzzle is the “Florida Bungalow Syndrome”.

If any of y’all can come up with something that fits as well or better I’m willing to listen… but it needs to fit as well or better.
 
Just an idea... have you tried smaller splits oriented with more air space? This is what I have to do when it's arctic out. Bigger splits don't put out enough heat fast enough and without the airspace between them the coals tend to pile up on me.
 
Quote from Spidy
"…and it also explains very well why some of us have problems similar to mine, while others of us don’t. Basically, the closer conditions are to test conditions the better these EPA stoves will work, but as conditions move away from test conditions the worse they will work… and the degradation in performance ain’t linear. If my fire box was sitting on the main floor of a single story, ranch-style home, in a slightly less cold and windy area of the country I’d likely be singing its praises… but living where I do, in the type home I do, I’ll never get close to the performance I need when January rolls around. It-is-what-it-is… it’s all about having the correct tool for the task at hand."

that very interesting to me since i started reading that and i was half wondering if you would be calling me out on that since i fit that exact scenario. Ranch house, single story, less cold and windy with a 13-15 ft chimney.

i have heated my house 100% with wood for years now and my NC30 stove has been great.

at least with my setup though that i have had for about 8 years now i have noticed one thing completely opposite that you have mentioned. when the weather warms up on the shoulder season my EPA stove heats less. my stove will noticeably slow down the wood consumption with the same draft settings if it is single digits to teens vs a warmer 40's deg day.

i attributed this to draft and the greater temp difference pulled a stronger draft up my chimney running my stove hotter in the colder weather.

most assemblies are made to run in a certain "sweet zone" i can believe that the EPA has steered wood stove manufacturers to heat under certain laboratory conditions. Sounds like you are truly outside the parameters of what they spec'd the stove to run with. although i find it hard to believe that they would test a stove to run on a 80 deg day the theory seems to fit. this coming from a pointy hat engineer who works in R&D (nothing related to stoves though). Just my 2 cents worth

most assemblies are made to run in a certain "sweet zone" i can believe that the EPA has steered wood stove manufacturers to heat under certain laboratory conditions. sounds like you are truly outside the perameters of what they spec'd the stove to run with. although i find it hard to believe that they would test a stove to run on a 80 deg day the theory seems to fit. this coming from a pointy hat engineer who works in R&D (nothing related to stoves though).
 
You're still beating this dead horse, eh? You're stove has too low an output capacity, especially as you have it set up. The manufacturer says it can only maintain a secondary combustion for 1/3 of the burn, and clearly its max output is specified during that time. After the secondary combustion ends its output will be lower by at least 1/3.

Further, you've said you are hauling buckets of unburned coals out of it, so you are throwing away a significant portion of the BTUs. If indeed you are "using" the same amount of firewood then this stove us using less, as you are throwing some of it away.

You say it becomes less efficient and burns more wood when the temperature drops - no kidding, you have the thing wide open and modified (opened) the firebox and removed the firebrick, but still usually only have coals. That is because your bizarre flue has poor draft, and when you finally get a decent draft going in cold weather it burns everything up and sends the heat up the flue because it's basically just a big open steel box now.

My "EPA" secondary combustion stove is in the basement with a well insulated single tube stainless steel 6" tube rising 30'. There are no dampers or draft controls in the flue. When it gets colder out the thing pulls like crazy, allowing me to stop down the air control farther and get some fantastic burns - great roiling blue plasma over the wood and heat outputs that are almost scary. After the the more volatile stuff cooks off I have to open the air control some to keep it going, and if I don't add anything then eventually I'll have to open it wider and there will be little secondary burn. This is fine because the stove is surrounded by lot of stone, and usually the room is way too hot and I can let that stone re-radiate the heat it has stored.

The stove is a US Stoves magnolia made of welded sheet steel, and has a single inlet control that limits BOTH primary and secondary air. It's sealed and I can pretty much shut off the air inlet, otherwise I could not keep it from running away. When I get it overfired and shut off the inlet I can see every place where the gaskets or window seal are leaking even a few molecules oxygen into the firebox - there is a small flame tendril showing me exactly where it is.

You can whine all you want but stoves of this type can work very well, with lots of heat output and efficiency, and they work best with strong draft. That does not mean they are all equally good, and if you have a strong flue you better make sure the stove limits BOTH primary and secondary air or there will be no way to control it.
 
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Spidey, I'm gonna have to agree with bits and pieces from the others. Mainly: Your stoveace is too dang small, leading you to feeding it too often in cold weather, which causes lots of coal buildup.

What I've learned with my new stove is that it's a balancing act of settings and fuel load to get it to do what you want. You can't fill it full and expect to burn it down to nothing in 3 hours (like I could in the old stove) and transfer ####-tons of heat into the building. I used to do this, get the basement hot to the point of unbearable, then fill, damp back and leave for 10-12 hours to come home to comfortable. With the new stove, I have to use a little propane (about a gallon or two a day - estimating use based on tank guage - about 40 gallons used including hot water and 4 days on full propain while I was up north fishing since my install in late Jan.) to maintain "comfortable" at the end of a long period away from home. The old stove wasn't better at keeping me warm, it was better at pure WOT heat output, much of which would be stored in the thermal mass of the house to make up for the heat it wasn't putting out toward the end of a long burn. The new one just pumps out a lower quantity of even heat over that period, something you've alluded to before.

After my experience with a 3.4 CF stove, it's rating of 2,400 sq ft is probably only realistic until you get down around 0, or have a well insulated home. (I'd call mine just slightly below average, but more insulated than what you have). A 2.1 CF stove like your Spectrum could only be rated to heat 2,000 sq ft somewhere where they have signs that say "bridge may freeze in winter". Up here, I'd consider a stove that size to be good for 1,200 or so? Glad I bought the big one, and didn't get that one from you in hindsight.

Hope the Daka works well for ya, and we can be done listening to the high pitched whine coming from the Iowa river bottoms.
 
Well, for somebody that’s never seen it, you sure do know a lot about my chimney and its ability to draft WoodHeatWarrior… you must be clairvoyant, huh? Or maybe you traveled with Santa Clause last Christmas and dropped down all those chimneys.

The problem has never been poor draft… ever! And for you, or anyone else, to preach to me that I have a poor draft problem, when you’ve never seen the damn chimney is flat arrogant, audacious, and bigheaded of you. If there’s a draft problem it’s because there’s too much draft, not because there’s too little… and that’s a damn fact whether you want to accept it or not. You could pull the pipe from the chimney collar and have your hat sucked off your head… and you’d eventually find it a couple hundred yards out in the woodlot. If I have such a poor draft problem why is it, on a cold day, I can open the firebox door with the flue damper completely closed… and not get even a whiff of smoke in the house? Why is it, when it’s 50[sup]o[/sup] outside I can close the flue damper something more than half way and still not get any smoke in the house when I open the door? Why is it I can take a piece of tissue paper, place it on the floor of an ice-cold fire box, and when I let go of it I can watch it fly up and out… and actually have someone stand outside and watch it exit the chimney? Try that experiment with your stove… I’d love to hear about the results. I’ve opened the cleanout door on the floor in mid-summer and watched it suck a piece of notebook paper off the floor (placed there to catch any soot that might fall) and send it out the top of the chimney (weren’t no need to worry about soot, it sucked it all right in). It ain’t poor draft… get over it already.

And I ain’t “modified (opened) the firebox” in any way… where do you get that idea? I run the draft setting wide open because it’s not needed using the flue damper. The flue damper chokes back the fire way more than the stove draft adjustment ever did (not to mention it works one heck of a lot better). Most days, with the damper set a bit over half way the draft adjustment makes absolutely no noticeable difference in combustion at any setting… because even at its lowest setting it would allow more air in than the flue damper will.

So… “the manufacturer says it can only maintain a secondary combustion for 1/3 of the burn”. How long should that be? How does around 45 minutes sound to you on an extremely cold day? Let’s see… 45 times 3… hmmm…. so I can expect around 2 hours and 15 minutes total burn cycle… correct? Well guess what? That is about what I get before the thing quits heating. I didn’t say before the heat output reduces, I said it quits heating… I can lay my hand on the bare metal stove front, but the flue is screaming hot.

You seem pretty sure of yourself for someone who doesn’t have even a fraction of the facts… and the facts you think you have are incorrect. I’m glad your stove makes you sweat… good for you… but yours ain’t mine, your setup ain’t mine, and what you think you know has nothing to do with mine. My stove does not have, as you say, “too low an output”… it has NO OUTPUT! NONE! After the secondary shuts down any heat it’s making just goes out the damn flue… even with the damper closed. That ain’t a friggin’ “poor draft” problem!
 
What I've learned with my new stove is that it's a balancing act of settings and fuel load to get it to do what you want. You can't fill it full and expect to burn it down to nothing in 3 hours (like I could in the old stove) and transfer ####-tons of heat into the building. I used to do this, get the basement hot to the point of unbearable, then fill, damp back and leave for 10-12 hours to come home to comfortable.

Steve, I didn't do that with the old stove (heat to the point of unbearable, then refill), there's near always someone at home to maintain the thing... we just kept the house at an even 70-72[sup]o[/sup]. I couldn't make the old one burn down in 3 hours without melting it down at the same time, but this new one will burn down to a bed of coals in three hours... a bed of coals that do not heat! Don't you guys get it? I can lay my hand on the bare steel of the stove when it stops heating... even with several inches of coals in the box. Y'all need to quit looking for simple, traditional answers to this... it ain't simple, and it ain't traditional. In fact, most of the time it don't even make sense.

Listen, I agree I'm not using it as it was intended to be used...
But even so... how I'm using it does not explain what's happening... it just flat don't.
 
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In fact, most of the time it don't even make sense.

You got that right! You're not gonna touch my stove with a bed of coals in it - 300-500° stove top temps even at the end of the cycle. I'll take a pic when I get home tonight. Just filled up 10 minutes ago.
 
You got that right! You're not gonna touch my stove with a bed of coals in it - 300-500° stove top temps even at the end of the cycle. I'll take a pic when I get home tonight. Just filled up 10 minutes ago.

I believe you...
Heck, after what I've been through, right now I'd be tickled pink if mine ran anything over 150[sup]o[/sup] when it got cold outside.
 
OK, I went back and read your old post, and the holes you drilled were not from the outside, so I was wrong about that part. However, you've said you keep the air control wide open and it still burns down to coals and is not hot. No way it would do that with a good draft and the air control open - all the air manifolds and stuff are pretty much irrelevant with the primary air control open, it's really just a steel box with a big inlet and outlet hole in it at that point. If you think the draft is good then you have to explain why the coals don't burn up.

If I tried that with mine, even ignoring the massive overfire there would be nothing left but some ash in short order. Lots of air flow through a steel box with burning wood in it tends to do that - what exactly do you think is happening in the mystery stove?

As for the chimney damper, by using that you are forcing the secondary combustion off. Without a damper, restricting the primary air inlet forces the air to flow through the secondary manifold (which is more restrictive). If you limit the flow with a damper on the output then from the stove's point of view there is less draft, which can easily flow through the open primary path and there will be no reason for it to flow through the (more restrictive) secondary path. The reason these things like a strong draft is because it's quite restrictive trying to get air to go through the secondary air manifold and flow out the little holes with any kind of velocity. With the primary open and draft limited on the output you are bypassing the secondary.

Anyway, the problems you are having are not at all universal. There are many of us who do not have these issues at all with "EPA" secondary combustion stoves. Lots of heat and less wood use. I don't really need to diagnose your system, it's too messed up to bother with. I'm more interested in countering your constant complaints about these types of stoves so other people reading this don't get the idea that your system is typical and that these stoves don't work. They do, or at least many of them do.
 
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Sorry, but around here according to a dealer. spideys problem with a stove in the basement is very frequent. Some places recommend NOT putting one in the basement for that reason. Only on the epa stoves.
 
Sorry, but around here according to a dealer. spideys problem with a stove in the basement is very frequent. Some places recommend NOT putting one in the basement for that reason. Only on the epa stoves.
We've discussed quite a few different problems here and I'm not sure which one in particular you are referring to. The problem of too much draft causing an over fire that cannot be properly controlled when there is only a primary air control?
 
Good thread lots of good posts... I dont want to regurgitate what most of you have written so far but here's a few observations:

* As many mentioned wood is a non standard fuel burning in a non-standardized environment variables (draft, chimney lenght, house insulation, barometric pressure etc...) this is opposed to modern furnaces (oil, gas) they have controls and powered motors and electronics to deal with. User experience will vary from fire to fire since the variables are constantly changing.

* Also user experience will vary from user to user. Two user might have the same model one will love it and one will hate it.

* BTU output stated for any wood stove is on high fire. This is only maintained for 1 hour at best. Wood burning cycle is a bell curve. ie. it starts low, peaks then lower down again.

* It's a 'zone heater' ie it has no means of transporting heat from here to there. (unlike a forced air furnace). You have to help it along.

* Square FT rating is all baloney. We use it because the customers demand it but there is no science to it. Rely on the cu ft of the firebox. The bigger the firebox the more heat. How it covers Sq ft is entirely up to you.

* EPA testing has no efficiencies attached to it. It's all about emissions (pollution). This testing is done with cribbed dimensional lumber in small QTY.

* However, most mfg test their unit with mix hardwood to approximate real life burning and from that they get their BTU & efficiencies rating.

* Efficiencies testing for wood stove uses the 'stack loss' method. This works quite well... Whatever heat is lost up the flue is deducted from the over BTU output. Therefore, if stack loss is 20% of the BTU output then the unit is 80% efficient.

* I've met John Gulland. Very knowledgeable guy and he wrote part of our manuals on how to burn wood.

Spidey, 40 ft chimney is very tall. I have a 30 ft chimney and I've gone crazy with my insert insulation. Therefore I have a fantastic draft, actually overdraft. It burns hot and fast, & I did modify some of the air intake as well to slow things down.

We're working on some electronic monitoring system as an option to make stove more automated to balance the output of wood stoves.

Guys, no need to get our underwear in knots over this. It's wood burning... One of its charm is it never twice the same. If you want good regulated heat output there are many oil furnaces available for cheap on Craiglist.
 
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We've discussed quite a few different problems here and I'm not sure which one in particular you are referring to. The problem of too much draft causing an over fire that cannot be properly controlled when there is only a primary air control?

On units that have the over fire secondary. most stoves as you close the primary, you reduce the secondary. But the secondary stays open at a min setting. So when there is a draft to great, it pulls to much air thru the secondary. Causing a hot quick fire then leaving a large coal bed that won't burn down because the air is only coming thru the secondary. In effect whisking the heat from the top of the stove out the chimney. The place that doe's not recommend these stoves in the basement, suggests a cat stove for these applications.
 
If you think the draft is good then you have to explain why the coals don't burn up.
Oh c’mon man, we’ve been through this. It’s because the primary air comes in at the top and is sucked up the flue before it ever makes it down to the coals. I even tightly wadded up some newspaper and put it in the ash pan (the primary and secondary air enter from the same chamber as the ash pan) and lit it, closed the ash drawer and watched the smoke come into the firebox… it was sucked up the flue before it ever made it to the coals. You should see the glass in my door, the lower half has turned to an etched milky color… starting right where the air reverses direction.

…what exactly do you think is happening in the mystery stove?
It ain’t a mystery any more… it’s a serious overdraft condition (for this particular stove, anyway). If you sit and watch it burn it all makes sense. I get secondary burn flames shooting like a jet well down into the firebox (with the flue damper closed or open, or the draft control closed or open, or both closed or open) and it causes the fire to ignite on top and burn into coals rapidly. The coals collapse onto the wood and coals below (that ain’t getting any primary air to speak of) basically smothering them further. The problem is the suck is sucking harder than the intake can keep up with… most of the primary air just gets sucked out as soon as it enters.

As for the chimney damper… forcing the secondary combustion off… restricting the primary air inlet… secondary manifold (which is more restrictive)… limit the flow with a damper… less draft…no reason for it to flow… The reason these things like a strong draft...
Not according to the article I found, written by someone who should know (it appears). In fact, if you read it (the link is in the original post) EPA stoves are specifically designed to operate at the lowest possible draft so they can pass emissions testing at the low setting… because the low setting is where particulates would most likely be created and expelled… where it would mostly likely fail testing. But because they are not “air tight” (they can’t be or they’d fail testing miserably) they can be susceptible to overdraft problems under certain conditions. Don’t talk at me like I’m a child that needs a picture drawn to understand… and a picture drawn by someone who ain’t even seen the landscape to begin with…

Anyway, the problems you are having are not at all universal… I don't really need to diagnose your system… I'm more interested in countering your constant complaints about these types of stoves so other people reading this don't get the idea that your system is typical...
Did you even bother to read the original post? The link I provided? Cripes man, the whole point of this thread was to state my problems (very excessive problems) are not typical under typical conditions and typical installations. Although those problems manifest themselves because of the way stoves are required to operate during EPA testing. Because the EPA has placed a “one-size-fits-all” standard to certification… getting one to operate properly (even left totally stock) in the location I have mine installed will likely be impossible… difficult at best… it-is-what-it-is. That article in the link I provided is talking about and EPA certified stoves that are adversely affected by an overdraft condition in tall(er) chimneys during extreme cold weather… with the most common complaint from the owner/operator being extremely short burn times. Well I’m not your run-of-the-mill “common” owner/operator (most of us here are not), I can put two-and-two together and see what other symptoms that issue could create… symptoms the “common” guy wouldn’t think about or even notice. Cripes, the author of the article recommends that EPA certification be changed allowing manufactures to put adjustments on the stoves so a field installer can make adjustment for specific installations to eliminate such issues… adjustments hidden from the owner/operator.
 
We've discussed quite a few different problems here and I'm not sure which one in particular you are referring to. The problem of too much draft causing an over fire that cannot be properly controlled when there is only a primary air control?

My air control moves both the primary and secondary at the same time... and it will not completely close either one.
I've played with the linkage so the secondary doesn't open as far, and that helped some... for awhile, until it got really, really cold out.
 

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