How do older wood stoves compare to the new "EPA Certified" models?

[brewmonster]

Actually...I have my chemistry straight...I was a Plant and Soil Science major and have read (actual scientific) studies on particulate emissions from the burning of wood and other cellulose material.
There aren't "many nasties" in wood smoke...however scientific that may sound.

ANYHOW.....

I told a guy today that I'd buy his Vermont Castings Defiant Encore catalytic stove tomorrow...anyone have any info on this model?
My dad and grandparents used to have Vermont casting Stoves which everyone loved, so I'm basically going off that.

Thanks,
Phillip

Yeah, well, my Dad had a '67 Pontiac that he loved but that doesn't make me want to drive one. Today's cars are safer, cleaner, more efficient and more comfortable, i.e. better in every way. Likewise with stoves. I've had nice pre-EPA cast iron stoves, including two Vermont Castings models, but I wouldn't have one now. If that Defiant you're talking about is in good shape and the you are willing and able to keep the cat in good working order, I guess you'll be OK. I've known people who ran catalytic stoves and never gave the cat a moment's thought, just let it go to hell and ran the thing in stinkpot mode for years on end. Please don't do that and then justify it by citing your bizarre notions about woodsmoke emissions.

 

[WidowMaker]

Kentukydiesel "There aren't "many nasties" in wood smoke...however scientific that may sound."

That's correct. There's not a significant amount of volatile compounds in wood smoke to damage your health unless you are breathing it all day long in a very smoke filled atmosphere.

The biggest culprit in wood smoke is "Particulate Emissions" 2.5 micron or smaller. Basically dust that clings to your lungs and your body finds hard to get rid of.

As far as the boxwood stoves available on the market they are classified as 'EPA exempt' because their air/fuel ratio is above 35/1 - or for every pound of wood, at least 35 Lbs of air is consumed. In theory, this allows for a clean burn since the fire is so hot the smoke should be consumed as well. As with any theory it works well only if you are burning reasonably dry wood.

EPA will phase out this category in the next few years.

===

How do you measure a lb. of air ???Serious ?

 

[IHDiesel73L]

]How do you measure a lb. of air ???Serious ?

With the proper measuring tools. You can't put it on a bathroom scale but you can measure the weight of anything that has mass. All matter has mass. Air is matter. These discussions on AS are always interesting-slap "EPA certified" on something and some folks will run for the hills. It's pretty simple really-non EPA stoves send a lot of fuel in the form of VOCs up the chimney that either ends up as creosote or hot gas out of the cap. Those VOCs can be "re-burned" via secondary combustion so that you're making use of that fuel instead of venting it. Personally I wish my Englander was "EPA certified" because it would probably mean only having to cut, haul, split, and stack 3 cords a year instead of five. If you want to beat your head against the wall burning more fuel for less heat though, more power to you.

 

[Highbeam]

Establishing an emissions limit is one of the very few things I can think of that the EPA has done to help me. The limits are low enough that attaining them is done by improving efficiency. This is how it happened with cars prior to about 1996.

What will happen next, which is what happened with cars, is that the emissions will have to be much lower and then as with cars, efficiency will go down since mucho heat will have to be sent up the stack to clean up the emissions.

Ever notice how cars now have a very very hard time hitting even 40 mpg? Remember back when the old carbureted civics could get 50? How about the diesel trucks? The pre 2007 models got well over 20 mpg where the new ones get low teens.

There is a tipping point where the good times happen and for stoves that time is now.

 

[Chris-PA]

Carbon

With the proper measuring tools. You can't put it on a bathroom scale but you can measure the weight of anything that has mass. All matter has mass. Air is matter. These discussions on AS are always interesting-slap "EPA certified" on something and some folks will run for the hills. It's pretty simple really-non EPA stoves send a lot of fuel in the form of VOCs up the chimney that either ends up as creosote or hot gas out of the cap. Those VOCs can be "re-burned" via secondary combustion so that you're making use of that fuel instead of venting it. Personally I wish my Englander was "EPA certified" because it would probably mean only having to cut, haul, split, and stack 3 cords a year instead of five. If you want to beat your head against the wall burning more fuel for less heat though, more power to you.

Most of the energy we have access to is stored as a molecular bond of something with carbon. By burning it, we release the carbon and get (most of) the energy back that was stored when that molecular bond was made.

If you send stuff up the stack still bonded to the carbon, likely that was energy you didn't recover. If you can get it hot enough most of those bonds will break down into simpler molecules that are relatively harmless, and you get to use the energy. We all know how much energy goes into just collecting and moving the wood, whether it be our own physical labor (energy from food) or fossil fuel energy - you don't get that back directly as heat, it's just the cost of gathering it, and I sure don't want to expend any more of it than I have to.

I love my EPA stoves, one welded steel and the other cast iron. Unlike what's been described here they are both marvels of simplicity. They don't have complex systems or sacrificial parts (other than perhaps seals and firebrick), they work by virtue of the physical shape of parts made from durable materials. They are very effective and easy to live with day after day, and pleasing to look at. In the winter they are focal point of our lives, and after several years of this I still have fond feeling associated with them - they simply work and don't demand much of me. Certainly by spring I'm tired of the routine, but that doesn't extend to the stoves.

Both wood and fossil fuel are pretty much all solar energy, it's just that the FF was solar energy that fell a long time ago, while the wood we burn is solar energy from recent times - so when we release that we're making little net change to the amount of carbon in the air over the short term.

 

[Fyrebug]

Good post WoodHeatWarrior!

Burning wood is more or less carbon neutral. A tree stores its carbon in its trunk, so if it rots in the forest or if you burn it, it will release approximately the same amount of carbon. Better to make it useable by burning it.

Of course, we are not factoring the carbon required to power the chain saw, truck etc...

 

[TJ-Bill]

I upgraded my old Fischer to a new huge EPA monster. The new stove takes a 24" piece of wood and the fire box is used in the larger furnace models. I still find that the old stove heated the house better then the new one. Yes the new stove has a fancy blower, a double burn chamber and yes it's air tight and has longer burn time, and yes most mornings I can just come down stir up the coals throw in some wood and walk away but when the sided of my old stove started to glow red you knew you were opening the bedroom that night.

anyway my insurance company is happier..

 

[kah68]

Good dry wood, straight and tall chimney and a good EPA stove is money in the bank! Between 6 mo. to 3 year pay back when you factor in money saved in Oil and Gas. I went from buring over $3500 a year in oil to $1000 in oil and $500 in wood (My own supply).

 

[WidowMaker]

With the proper measuring tools. You can't put it on a bathroom scale but you can measure the weight of anything that has mass. All matter has mass. Air is matter. These discussions on AS are always interesting-slap "EPA certified" on something and some folks will run for the hills. It's pretty simple really-non EPA stoves send a lot of fuel in the form of VOCs up the chimney that either ends up as creosote or hot gas out of the cap. Those VOCs can be "re-burned" via secondary combustion so that you're making use of that fuel instead of venting it. Personally I wish my Englander was "EPA certified" because it would probably mean only having to cut, haul, split, and stack 3 cords a year instead of five. If you want to beat your head against the wall burning more fuel for less heat though, more power to you.

===

I'm beating my head against nothing,but you seem to be, I do burn a EPA stove. I was simply asking a question. Then I done some googling and found lots of information, but it all have me a headache reading it and I still don't know how they can determine their 35 to one ration of air to fuel...

 

[IHDiesel73L]

I'm beating my head against nothing,but you seem to be, I do burn a EPA stove. I was simply asking a question. Then I done some googling and found lots of information, but it all have me a headache reading it and I still don't know how they can determine their 35 to one ration of air to fuel...

My post was not directed at you-it was directed at others on AS who treat EPA certified stoves like the boogeyman. Here is a Wikipedia article that explains air-fuel ratios with regard to liquid and gaseous fuels, but it's the same idea:

Air

Every fuel has an ideal ratio of fuel to air for a complete burn.