Longer Burns vs. Efficient

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04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
I am a newbie to wood burning and found this on jotuls website and it has me stumped especially the last line.
http://jotul.com/us/home/pre-epa-airtight-stove-vs-non-catalytic-clean-buring

"Non-catalytic woodstoves use secondary combustion air in order to burn off wood gases before they can leave the firebox. Because of this, they are not as controllable as a pre-E.P.A. “airtight” woodstoves. It was possible to “turn down” a pre-E.P.A. woodstove and achieve a long low smoldering fire. This was often perceived as being highly efficient. From an emissions viewpoint nothing could be further from the truth. From a user-friendly viewpoint, I fully understand why this was perceived as being efficient. For example, let’s load a non-catalytic woodstove with six sticks of wood. Over a period of 4 hours let’s say it produces 30,000 btu’s of heat per hour with less than 7.5 grams of particulate emissions per hour. Now let’s load the same six sticks into a pre-E.P.A., “airtight” woodstove. This stove may burn for 8 hours producing 10,000 btu’s per hour with around 80 grams of particulate emissions per hour. 4 X 30,000 = 120,000 btu’s; 8 X 10,000 = 80,000 btu’s. You see a difference here of nearly 40,000 btu’s. The E.P.A. stove has produced more heat from the same amount of fuel. The “airtight’ burned longer (more controlled) than did the E.P.A. certified stove but wasted 40,000 btu’s of energy up the chimney in the form of wood smoke (unburned wood gas). Some of it went into the environment and some of it condensed in the form of creosote in the chimney. I’m making numbers up but under the identical conditions (same chimney, same house, same fuel, different stoves) these numbers are accurate. An E.P.A. certified woodstove should produce about the same amount of heat with a third less wood than an old “airtight” but it does it at a price. It will burn much faster and for a shorter period of time than the old “airtight”."

If that last line is true why do so many on here say they get longer burn times?
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,812
Michigan
Simply because that is what we are getting. Not only longer but hotter. For example, in our old airtight stove we usually burned 6 cord of wood per year with the highest being 7 1/2 cord. We closed off part of the house and were never really warm once the temperature got below about 15 degrees.

Fast forward to the Woodstock Fireview, a soapstone stove with a catalyst. The Fireview is a much smaller stove but still, we no longer had to close off part of the house. Our wood needs dropped to 3 cord per year and the house was much, much warmer. After a few years we did some remodeling, adding insulation, new doors and new windows. We even added a room. We still no longer close off any part of the house and we keep the house around 80 degrees all winter long. So far the coldest we've had with this stove is around -14 outdoors. That morning I think the house was 78. Don't remember for sure but our house rarely will go below 76-78 during the winter months.

Quite naturally this year is a colder winter and the cold for a longer period of time and we will be curious to see how much wood we'll burn. At present, it appears we are still going to be around 3 cord.
 

04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
I wonder why jotul says this then. Also, what about the user friendly part opinions?
 

Hogwildz

Minister of Fire
That last line is bullshit. Older stoves are loaded often, burned hot, and eat wood like a Russian woman at an Old Country Buffet.
As far as I am concerned, about all of those statements are pure BS, except for a Pre EPA being shut down and smoldering.
 

04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
Thats where I am confused doing all the research on the hearth everything tells me to go epa. But this from jotul and a few other sources make me think not to?

Also, I do believe the user friendly part because people that have non epa just open the damper open for a few minutes then close it to where they want regardless of the temps outside the device works the same.
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,812
Michigan
Well said Hog.
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,812
Michigan
Thats where I am confused doing all the research on the hearth everything tells me to go epa. But this from jotul and a few other sources make me think not to?

Also, I do believe the user friendly part because people that have non epa just open the damper open for a few minutes then close it to where they want regardless of the temps outside the device works the same.
For some more information, try looking here: http://woodstove.com/
 

04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
I am familiar with this site but other sites disagree so I am just spining my head right now.
 

Backwoods Savage

Minister of Fire
Feb 14, 2007
27,812
Michigan
I am familiar with this site but other sites disagree so I am just spining my head right now.
For sure, most manufacturers tend to put a lot of hype with the stoves, after all, it sells more stoves. I think you will find that if anything, Woodstock will be a bit more conservative with their information. Perhaps this is because they are direct sales rather than showroom sales. No need to hire high pressure sales people or fast talkers.
 

04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
Thats a good point savage did not think of that.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,123
South Puget Sound, WA
I didn't get a sense of marketing from the quoted paragraph. It more sounded like a salesperson or tech trying to clear up some confusion. Unfortunately the person only got partial facts down and got stuck in generalities that don't always prove true in the real world. He never covered the difference between wood species and moisture content which are major influences. Nor did he cover the affect of draft on new vs older stoves. And he (or she) generalized about efficiency which can mean several things in the stove world. So a weakly written article agreed, marketing, not really. Woodstock is not the only low key company out there. Kuma, Blaze King, Enviro and others all take a pretty low key approach.
 

04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
Begreeen you mentioned draft does that mean that the old pre epa does not need a strong of draft compared to epa?
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,123
South Puget Sound, WA
Correct. There are no tubes to pull air through in a pre-EPA. They can burn with pretty short chimneys whereas a non-cat EPA stove uses the draft to pull the air through the secondaries for reburn.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,123
South Puget Sound, WA
You may not need it, but others in the room would appreciate some exhaust, other than your contribution. ;sick:)
 
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jatoxico

Minister of Fire
Aug 8, 2011
4,216
Long Island NY
I think what the site was saying is that you could really smolder a fire with a pre EPA airtight more so than the newer stoves. You didn't get any heat and it was a creosote factory if you did but you could smolder a fire. So yes if you shut a pre EPA stove down tight it could burn longer than a non cat EPA stove.
 

rideau

Minister of Fire
Jan 12, 2012
2,168
southern ontario
Simply put, the burn times in that "article" are inaccurate, but the efficiency and cleanliness are not. EPA beats non-EPA hands down in efficient use of wood and cleanliness. And EPA stoves are not difficult to run. There is a learning curve to get maximum efficiency out of the varied stoves, which is nice because if you care enough you can run your stove very efficiently. But even if you aren't too interested, if you feed the stove dry wood and just take the time at the beginning of a burn to get the fire started well, with an amount of air that gives a good burn without an inferno, you'll do just fine and have a more efficient stove than a pre-EPA.

If you are not going to burn dry wood, by all means get a pre-EPA an clean you r chimney every two to four weeks for maximum safety.

It is really pretty hard to argue against EPA stoves being the environmentally and financially sound way to go.
 

ddddddden

Minister of Fire
Oct 20, 2009
1,487
Central Va
Non-catalytic woodstoves. . .are not as controllable as a pre-E.P.A. “airtight” woodstoves. It was possible to “turn down” a pre-E.P.A. woodstove and achieve a long low smoldering fire. . .
I think the author's purpose is to address the air control of EPA non-cats. Here's a better article:
http://www.gulland.ca/florida_bungalow_syndrome.htm

Basically, the EPA mandated that the air supply must remain open a certain amount on non-cat stoves, because a catalyst is necessary to burn cleanly at smolder temps. For the user, the pracical result is that, if you want less heat, you load less wood, because you can turn down the air only so far. . .and this is when you will get a shorter burn time.

There is no question that newer stoves are more efficient than pre-EPA's.
The big question is: Would you like to burn less wood?
Second question: Do you have/can get dry firewood?
(Secondary burn is hard to achieve with relatively wet wood that people think is "seasoned.")

p.s. The third option, referred to by Mellow, is a catalytic stove, on which the air can be turned down more than a non-cat. . .dry wood is still required though.
 
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jatoxico

Minister of Fire
Aug 8, 2011
4,216
Long Island NY
Correct me if I am wrong but I think the article is accurate. Thinking of it as an equation.

If the amount of wood is fixed (6 sticks) than a completely shut down pre EPA stove can burn longer while producing less heat than a new stove BUT...

If we fix the BTU's (120K) and ask both stoves to put out that amount of heat the EPA stove can do it with less wood or if we use the same amount of wood the EPA stove will burn longer AND...

If we set time (say 6 hrs) as a fixed amount the EPA stove can do it with less wood.
 

Charles1981

Minister of Fire
Feb 19, 2013
762
Michigan
It might be able to smolder longer but again it is smoldering. A smoldering fire is not producing any beneficial heat. We have all had fires that got shut down to fast or threw in some wet wood. Everyone hates a smoldering fire.
 

tarzan

Minister of Fire
Jan 16, 2014
1,552
wv
It might be able to smolder longer but again it is smoldering. A smoldering fire is not producing any beneficial heat. We have all had fires that got shut down to fast or threw in some wet wood. Everyone hates a smoldering fire.
Not everyone hates a smoldering fire. Many people stuff big old pre-EPA stoves full, get the fire caught up, "shut er down" and do it again ten to twelve hours later. This is actually the way I thought it was supposed to work for many years. So glad I thought there had to be a better way.
 

04HemiRam2500

Feeling the Heat
Jul 10, 2013
426
SW PA
Well I am thinking that the biggest thing is how good the wood is and your draft. A weaker chimney like mine will be better off with a non epa appliance. Also, many on here have been able to get secondaries with a non epa it is harder but possible. So I am sorry if I am going against the curve but I see a non epa as a better choice for me anyway. I have tried otherwise and no dice.

I think the other thing to note is as far a furnaces go you are able to take a non epa and get it almost smouldering and still heat your house. Of course outside temps and creasote and dry wood are all factors. But, the blower on a furnace can move that smaller amount of heat around your house easier.

Again, I am just one of the few I guess that likes the non epa. The are other on here that do feel the same you too.

Also, I know many on here state they use less wood with an epa. I think that is true under certain conditions such as house size insulation, if it is a stove or furnace etc. I do believe that there are non epas that would use the same amount of wood that an epa appliance wood. If not I think it would be darn close. Within a full cord 128 cu ft.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,123
South Puget Sound, WA
Not everyone hates a smoldering fire. Many people stuff big old pre-EPA stoves full, get the fire caught up, "shut er down" and do it again ten to twelve hours later. This is actually the way I thought it was supposed to work for many years. So glad I thought there had to be a better way.
Beneficial is conditional. If it is a big old 5 cu ft stove and you fill it then smolder you could very well have plenty enough heat to keep the house warm and a stove chugging along at 300-350F.
 

tarzan

Minister of Fire
Jan 16, 2014
1,552
wv
Beneficial is conditional. If it is a big old 5 cu ft stove and you fill it then smolder you could very well have plenty enough heat to keep the house warm and a stove chuggiandng along at 300-350F.

Unless It's a single wide trailer, then 3 cubic feet is fine!:) I'm not going to go into details but believe me, I can relate to Denises post a couple days ago. Many in my area have very poor burning practices and to top it off this is coal country so anything with EPA attached to it must be bad.
 
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