Effectiveness of secondary burn in EPA stoves

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MnDave

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I just replaced a non-EPA stove with an EPA stove. The first thing that I noticed was the ceiling of fire in the EPA stove. My non-EPA stove did that for 15-20 minutes max during less than half of the burns.

My new EPA stove has the ceiling of fire effect non-stop until all the gasses are burned and the coal stage starts. I am very impressed. One, because it is beautiful and two, because it means that I am burning more efficiently and with less pollution.

Do you think that the newer EPA stoves with secondary burn tubes do a pretty good job of burning the gasses?

How effective do you think this is at reducing the potential for creosote to develop?

These are lead-in questions. Once I get some comments (hopefully), I will follow up with where I want to go with this.

Respectfully,
MnDave
 
What type of stove (make and model) do you have and what type of wood are you burning (how long.split and seasoned)?

Welcome to the Forums
 
I just replaced a non-EPA stove with an EPA stove. The first thing that I noticed was the ceiling of fire in the EPA stove. My non-EPA stove did that for 15-20 minutes max during less than half of the burns.

My new EPA stove has the ceiling of fire effect non-stop until all the gasses are burned and the coal stage starts. I am very impressed. One, because it is beautiful and two, because it means that I am burning more efficiently and with less pollution.

Do you think that the newer EPA stoves with secondary burn tubes do a pretty good job of burning the gasses?

How effective do you think this is at reducing the potential for creosote to develop?

These are lead-in questions. Once I get some comments (hopefully), I will follow up with where I want to go with this.

Respectfully,
MnDave
It sure does help with wood consumption , pollution and creosote!
 
I'm always impressed when my stove is up to temp and I go outside and look at my chimney and I see NO smoke. Such an amazing improvement over my open fireplace...add to that the heat my insert puts out and how long a load of wood lasts and how can you NOT have a modern EPA stove/insert in your house????
 
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Do you think that the newer EPA stoves with secondary burn tubes do a pretty good job of burning the gasses?

How effective do you think this is at reducing the potential for creosote to develop?

If these things didn't work, I wouldn't have gone from burning 5.5 to 6 cord a year down to 4 to 4.5 cord and have a warmer home on average.

The chimney has definately stayed cleaner as well. It's been a win-win-win (when you consider that I sold my pre-epa stove for enough to pay for the EPA stove)

I often wonder if the stove manufacturers would have ever gone this route without the mandates of the EPA. I also wonder if the EPA envisioned secondary burning technology, or if they were planning on every company going to a cat style stove.

pen
 
Welcome! Yes this technology does a significant job at reducing creosote build up. Most of us 24/7 burners have to sweep once a year. My biggest problem is the chimney cap where the gases hit the cold air. I can't imagine how often I'd have to clean that if I was running a pre-EPA stove.

During the day, take a look outside at the chimney during a cold start and see the smoke pour out. Then turn the air down and watch the secondary burn tubes engage and go back outside and compare how much less smoke is emitted.

My first stove was a Hearthstone Homestead and the fire show was out of this world. I have a catalytic stove now, Woodstock Fireview for the longer burn time. I don't have to push the stove as much when it gets really cold either. The light show is not as spectacular, but still enjoyable. I've cut my wood consumption by about 25%/year.
 
Not for nothing I do get more crap at my screen on the cap then I like after a season..not much elsewhere..but more on the screen then my old smoke dragon bk..go figure..must be the lower stack temps of a cat burn.
 
Less is more...less smoke, less creosote, less wood consumption = more heat, warmth, and efficiency.
 
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What type of stove (make and model) do you have and what type of wood are you burning (how long.split and seasoned)?

Welcome to the Forums
Thanks Dexter. I have a Quadra Fire 5700 on a 25 foot Class A chimney.
I burn mixed, about 60% soft (birch, aspen, basswood) and 40 % hard (oak, cherry, elm). This years has been good. I am finally getting ahead because of the mild winter following a very cold winter.

I burn 2-3 full cords a season. I currently have 6 full cords, 3 cut and split and 3 just cut. Most was standing dead. It is pretty dry. I cover it from rain. After reading this forum I plan to season more so I need to get ahead and stay ahead. I can do that. I get my wood free from neighbors and the trees around here are pretty good size.

MnDave
 
Great responses. Again, I'm new to EPA stoves with their secondary burn tubes.

So here is the "real" question.

I currently use a stovepipe gauge and adjust the burn rate to keep the stovepipe temp above the creosote range. This seems "pre-EPA". Since my new EPA stove burns these gases in the stove, the stovepipe is no longer my control point, the stove is.

So, should I just use a stovetop gauge and adjust to keep that above the creosote range? The reason I ask is that would allow me to decrease the burn rate and increase the overall efficiency. The chimney would run 50-75 F cooler and the draft would consequently drop some but who cares?

How many here just operate using a stovetop gauge? What temps do you control too and why?

Thanks,
MnDave
 
I use a stovetop gauge only. It tells me when to engage the cat. It also tells me if I am nearing over firing the stove soapstone. Recently I've learned that it helps me to figure out when to decrease the air to help stabilize the stovetop temp.

I am not concerned about creosote build up. I sweep the chimney once a year. I may have to climb on the roof one more time and clean the chimney cap. Usually I know its time because draft suffers and smoke leaks into the room when I open the stove door on a reload. My wife is very frosty to this, unfortunately.

If you need more heat because its very cold out, burn aggressively. If you don't have to, burn efficiently. Efficient burning will reduce creosote, save wood, and still keep you warm.
 
Stovetop gauge only, run 450-600 most of the time. Been known to hit 700 though. Secondary burn, very enjoyable, great show on right now!
 
I use a stovetop gauge only. It tells me when to engage the cat. It also tells me if I am nearing over firing the stove soapstone. Recently I've learned that it helps me to figure out when to decrease the air to help stabilize the stovetop temp.

I am not concerned about creosote build up. I sweep the chimney once a year. I may have to climb on the roof one more time and clean the chimney cap. Usually I know its time because draft suffers and smoke leaks into the room when I open the stove door on a reload. My wife is very frosty to this, unfortunately.

If you need more heat because its very cold out, burn aggressively. If you don't have to, burn efficiently. Efficient burning will reduce creosote, save wood, and still keep you warm.

Vic99,
I am still chuckling over your signature... expert wood scrounger. Ain't it the truth. My nickname is Woodhawk! hah.

Also, I am proud of you for taking note of your wife's like's and dislike's. It's hard to fully enjoy your woodstove if your wife is telling you that she is smelling smoke. My wife is my wood burning buddy she is my best friend (and more of course). She helps cut, haul, split, stack, move, you name it. She enjoys wood burning but I am a fanatic... and I run the stove ... and the TV.

That is very cool that you use a stovetop gauge as your control point and that creosote is not a concern. That is what I was wondering and what I was hoping to hear.

I do not have experience with a cat but I know what they are. It seems that they perform a similar function as the secondary burn tubes on a non-cat but my hunch is that a cat maybe better because it can handle a variable load of gas whereas the tubes are optimized or tuned (like a carburetor) to a particular range of gas flow.

I am amazed that after the gasses burn there is a distinct drop in flame brilliance signifying a drop in wood gas output rather than a slow change in the flame.

When it gets pretty cold here in Mn (we're talking -10 to -20 for a week or so) I just pile in the wood nonstop... survivor style. Of course that is between snowmobile runs.

I just found that my stovepipe gauge will not perform as a stovetop gauge. It must trap the heat and read too high. I have an IR handheld that gives me readings that I trust.

Enjoy brother,
MnDave
 
Stovetop gauge only, run 450-600 most of the time. Been known to hit 700 though. Secondary burn, very enjoyable, great show on right now!
NextEndeavor,

Very cool. Thanks for the temps. Do you do overnight burns? If so, any reason why you do not drop down into the 350-400F stovetop temps aside of good viewing?

Respectfully,
MnDave
 
I'm always impressed when my stove is up to temp and I go outside and look at my chimney and I see NO smoke. Such an amazing improvement over my open fireplace...add to that the heat my insert puts out and how long a load of wood lasts and how can you NOT have a modern EPA stove/insert in your house????
gd9704,
Yep, I have gone out to check on the smoke factor and thought about how the the old stove was a smoke dragon. I have orange streaks running down my vinyl siding from condensed creosote gases produced from that stove. Thankfully this comes off with muriatic acid but I have to wear a hazmat suit to dispense it without going blind and/or burning out my lungs. Hopefully my new EPA stove will correct this problem. Fingers crossed.

My neighbors are nice people but I think that they replace their stoves when the door falls off. If I talked to them about secondary burn tubes or cats their eyes would gloss over. But if I told them to check out my lack-of-smoke they would take notice. Most of us are outside here all year-round and when a stove is smokin we all smell it and it can make you sick.

MnDave
 
I often wonder if the stove manufacturers would have ever gone this route without the mandates of the EPA. I also wonder if the EPA envisioned secondary burning technology, or if they were planning on every company going to a cat style stove.

pen

Actually Earth Stove had a cat stove and secondary burn stoves before the EPA regs. There are many stoves that qualify for Oregon DEQ approval that are not EPA certified, but would likely pass EPA. Here is the list:

http://www.deq.state.or.us/aq/burning/woodstoves/DEQcertifiedStoves.pdf
 
Great responses. Again, I'm new to EPA stoves with their secondary burn tubes.

So here is the "real" question.

I currently use a stovepipe gauge and adjust the burn rate to keep the stovepipe temp above the creosote range. This seems "pre-EPA". Since my new EPA stove burns these gases in the stove, the stovepipe is no longer my control point, the stove is.

So, should I just use a stovetop gauge and adjust to keep that above the creosote range? The reason I ask is that would allow me to decrease the burn rate and increase the overall efficiency. The chimney would run 50-75 F cooler and the draft would consequently drop some but who cares?

How many here just operate using a stovetop gauge? What temps do you control too and why?

Thanks,
MnDave

I use a stove top on my Osburn, I try to keep it between 500 and 650. The secondaries are really nice, you should see a lazy wafing flame around those burn tubes if they look like raging flames ( afterburners) coming out of the tubes your wasting BTU's and wood, youll be burning clean but your going through your wood at a faster rate. You can control this by shutting down the air properly. I start to shut my air down when the stove top temp reaches about 400 degrees, I push the air in about 1/4 the flames will slow down and then I wait for the flames to get going again and push it in another 1/4 I repeat until Im about 3/4 closed and the stove top should be around 550 to 600 at this point with the lazy flames at the top of the firebox. I also will check my chimney as Im a new burner as well and this is my first year with this stove ( replaced a smaller insert with burn tubes this summer). For the all night burn I do the same routine I just add more wood for the longer burn and my temps are still around 550 to 600. I learned the other day do not over load your stove, do not fill past the top of the bricks, you need that couple inch seperation between the wood and the tubes that space is needed for the smoke to burn.
 
gd9704,
Yep, I have gone out to check on the smoke factor and thought about how the the old stove was a smoke dragon. I have orange streaks running down my vinyl siding from condensed creosote gases produced from that stove. Thankfully this comes off with muriatic acid but I have to wear a hazmat suit to dispense it without going blind and/or burning out my lungs. Hopefully my new EPA stove will correct this problem. Fingers crossed.

My neighbors are nice people but I think that they replace their stoves when the door falls off. If I talked to them about secondary burn tubes or cats their eyes would gloss over. But if I told them to check out my lack-of-smoke they would take notice. Most of us are outside here all year-round and when a stove is smokin we all smell it and it can make you sick.

MnDave

Don't worry . . . you're among friends here . . . we love to talk about this kind of stuff.

To answer your other questions . . . yes . . . the secondary burn helps reduce creosote . . . but so does the temp . . . of course there is a correlation I suspect between the temp needing to be hot enough with a secondary burner to have a secondary burn.

Like others I use a combination of the stove top and stack temp to properly run my stove . . .
 
Talk to them about producing more heat, cleaner and using less fuel to do it. Then shut up and let them be mesmerized by that nice clean glass and the beautiful fire view.
 
I know a guy that thinks drying wood is silly and when I tell him that my woodburner only smokes a little on startup and reloads he looks at me like I am a lying SOS.
 
NextEndeavor,

Very cool. Thanks for the temps. Do you do overnight burns? If so, any reason why you do not drop down into the 350-400F stovetop temps aside of good viewing?

Respectfully,
MnDave

Yes, overnight burn all the time when we drop into the 30s and lower. Above that I'm doing two cold startups/day and running on minimum inlet are to not run us out. Temperatures for over 8 hours will drop to 300 degrees leaving me enough coals for hassel free reloads. That temp will find the fan still running at getup time. I've never needed to fill the stove over 3/4 full.
 
I know a guy that thinks drying wood is silly and when I tell him that my woodburner only smokes a little on startup and reloads he looks at me like I am a lying SOS.

I know people like that also.
 
I use thermometers for both stove top and stack. You can get a lot of good info from both and fine tune your burn.
 
I read some where that old stoves were only 30% efficient so compare that with some newer designed stoves that are like 80% efficient.
 
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