Exactly what IS an EPA stove?

[REF1]

Environmental Protection Agency approved wood stoves. They pass a test on low emission particulates contained in wood smoke. The vast majority are non-catalytic. So, exactly what is a non-catalytic appliance?

The stove I now have is the Hearthstone Homestead. Non-catalytic. As I am renovating this house, I am currently coloring grout lines because the color of the grout is too light. So, I have been on my knees and able to actually spend time watching the cycle of burn in this unit. As some know I am not happy with the stove and have ordered a replacement for it. It's also a non-cat EPA.

This Homestead seems to have two essential features which make it different from non-cat stoves I have owned - a ceramic baffle, and three secondary combustion tubes at the roof of the box, front to back. I see no particular air stream paths that make it different from other non cat stoves I have used. The main air intake is a curse, to me, cutting a path through a load of wood generally leaving unburned chunks left and right. Not always, but enough to leave me frustrated in the morning, or as I watch logs on top fall into the door to burn as those beneath collapse in two pieces after being torched through the middle. That leaves a big ash mess when the door is opened and everything just falls forward. I know that's what lips are for. Still, other stoves I have owned made no such mess. I think the Fireview andirons are a decent idea.

So, is that it? The ceramic baffle and the burn tubes or some sort of perforated metal which jets secondary air into the firebox? And is that the common denominator in non cat EPA stoves?

In watching this Homestead closely, in running the stove at various settings, temps and load sizes I see no apparent effect of the ceramic baffle. The tubes show evidence of burning 'something' as the cycle moves along. There is no visible smoke in the box, save for start up when the tubes remain dormant. So, it becomes logical invisible, volatile gases are being burned in the jets of air from the tubes. But in my observations the only times the tubes are visibly burning those gases is when flames are shooting up into them. No flames, no visible jets of secondary combustion. The holes remain dormant until flames get to them.

While all this may pass a test for the EPA, logically, to my thinking and observation, if combustion activity is not forced through a secondary combustion zone or chamber, such as a catalytic zone, most of the smoke, gases and combustion particulates are traveling out the firebox exit (which in this case is the front top of the stove), moving across the underside of the top of the stove, and then up the flue. Perhaps there is manufacturing evidence/claim that is also a secondary zone, but it is not visible.

I have noticed fast, fully-loaded box, hot fires work best in this stove for cleanliness and full combustion of burn cycle. The manual of the stove I have coming (Pacific Fusion) states the same, save for a fully loaded box. Currently the unit is functioning at 500 with the draft half closed. But I'm also watching around 70% of the flames go right up the firebox exit. The back tube is dormant, the middle tube 60/40% involved in combustion and the front tube 70/30%, logically since most of the flames are exiting right in front of it. The observable percentages of secondary combustion do not seem very good overall. Most of this combustion is going straight out the exit and up the flue.

In watching the cycle of cat stoves I owned, those percentages were dramatically different, logically because all combustion - smoke, etc, were forced through the cat zone where they were observably consumed. The top of my flue showed that as well. No creosote tars, only small flaking at the end of a burning season. Thus far with this stove, after putting in a steel liner as well, the creosote is visible, though nowhere near as much as before the liner was installed. So, some benefit has been received, but only a small observable difference in burn cycle activity. I still get a face full of smoke when I open the door to reload. It's especially bad when I start a fire on coals and do not get my wood in the box fast enough. The first splits catch and before I get third or fourth into the box smoke is exiting the stove out the door. I find this firebox very difficult to load easily, mostly because of the shape of the firebox. My wood is 16-19% so it is sufficiently dry. The flue is now 17 - 18' up with two bends - into and out of the heart wall and up the flue. Seeing so many pics of that set up gives me evidence my flue is not unacceptable. Not a perfect straight shot up and out, but still quite acceptable.

I'd like other non cat owners to explain their firebox and draft systems and state what makes their EPA stove an EPA stove. After watching this one my camp yet settles in the catalytic field.

 

[REF1]

And there goes another log falling into the door.

I really hate this stove.

 

[Dakotas Dad]

So, is that it? The ceramic baffle and the burn tubes or some sort of perforated metal which jets secondary air into the firebox? And is that the common denominator in non cat EPA stoves?


I'd like other non cat owners to explain their firebox and draft systems and state what makes their EPA stove an EPA stove. After watching this one my camp yet settles in the catalytic field.

My limited understanding says that is it right there. We looked at a lot of stoves before our purchase, and all the non-cat solid fuel stoves had either a plate or tubes up there in the top, with holes for secondary air burning.

There are two main methods of meeting the EPA standards. One is by re-burning the smoke in a catalytic converter, the other is to re-burn it in the baffle burn tube chamber/area. Both are "secondary" combustion.. which cleans up most of the remaining particulates in the exhaust, just with different methods.

 

[begreen]

When in doubt, go to the source:
http://www.epa.gov/burnwise/woodstoves.html

An EPA stove is one certified to have passed the emissions requirements when tested. There are several ways to achieve this. They all involve burning off or reburning the unburnt wood gas. The reburn methods are primarily updraft reburn (using seconday tubes, manifold, or built in to the baffle), downdraft into a secondary burn chamber and catalytic. All 3 technologies work. Maintenance, performance over time, durability, cost are some of the variables that go with different designs. There are lots of very successful tube units out there, but it is more challenging to do this well in a shallow firebox. Some do it better than others, often by better methods of insulating the firebox.

 

[begreen]

And there goes another log falling into the door.

I really hate this stove.

Sounds like you want a stove that loads North/South and shouldn't worry too much about the burn technology. More important will be the clearances, how fast you want the stove to heat up the area, flue connector, wood capacity and burn times.

 

[REF1]

That's why I ordered the Fusion.

How does the Anderlea function?

 

[Dakotas Dad]

BTW, when you close your air, is the lever going all the way back to the leg? When we first burned ours, I thought we had too much draft, as I couldn't really slow the stove down even with the air 'closed" fully, but after I looked under the stove on day two, I discovered that there was a bit of a "soft stop" that I thought was the stop. Once I figured that out, the stove has been completely controllable and our burn times increased quite a bit.

and I don't know about the wood against the door thing, has only happened once that I know of, but I am pretty sure we rarely load it up to the "max" our full load is probably 70% of full in reality. the way we are running our stove, the only time we have flames a leaping the way you say, is just at first warm in the morning when we reload, then after 20 minutes or so, we turn the air down until we don't have all those yellow flames a leaping up and out, but just mostly blue flames that go up near the secondaries and burn. I linked a couple youtube videos in another post, (my first ever) that shows how our burn was going..

there is one at the top that shows what our stove is doing when I turn down the air, and one down a few posts that shows what it was doing much later...

https://www.hearth.com/econtent/index.php/forums/viewthread/53400/

 

[Todd]

If your getting smoke reloading the Homestead, I'll bet the Fusion will do the same since it's basically the same fire box design. This is where a bypass comes in handy like on the Lopi's and cat stoves.

 

[REF1]

Dakota, I have no problem shutting the stove down. The problem I have is lack of forceful air intake. Most of the time I have to crack the door to start a fire, even with fire starters. If anything I wondered if the draft control was messed up coming forward. But, it opens all the way.

Todd, Amen to a bypass system, man. I know they work well. I was worried about the same smoking problem with a Fusion until I looked at the manual and got some info elsewhere from users. The air intake system design isn't the same as the Homestead. I hope that makes the difference.

 

[REF1]

Todd, I wish you could see the stove at present. Log fallen to the front, basically cut in two. Left and right just sitting there, charred. Large split all the way in the back, on a big pile of coals, largely sitting there, not burning. The draft has been wide open for an hour now. All this wood in the box just sitting there. And this often the daily case with this stove. I know this is not typical with non cat EPA stoves operated by people on this site. But, 'tis the case for me. This stove, for whatever reason, just does not breathe very well.

 

[BrotherBart]

Exactly why I only burn N/S. Bed of coals in the front and a little space between the splits and hot stuff is gonna happen. Even on crappy draft days like today.

 

[Todd]

Todd, I wish you could see the stove at present. Log fallen to the front, basically cut in two. Left and right just sitting there, charred. Large split all the way in the back, on a big pile of coals, largely sitting there, not burning. The draft has been wide open for an hour now. All this wood in the box just sitting there. And this often the daily case with this stove. I know this is not typical with non cat EPA stoves operated by people on this site. But, 'tis the case for me. This stove, for whatever reason, just does not breathe very well.

I have seen it with my old Homestead. If manufactures are going to build a stove that loads E/W they should have a side loading door along with andirons to keep the wood off the glass. I also remember sometimes a log would roll down right in front of that dog house and screw up the whole burn and blacken the glass. I think you will be much better off with the Fusion and N/S loading.

 

[Dave_1]

Exactly what IS an EPA stove?

These folks can answer that by name.

http://www.epa.gov/Compliance/resources/publications/monitoring/caa/woodstoves/certifiedwood.pdf

 

[REF1]

Yes, I've seen that list awhile back. Had some companies I've never heard of before.

I was more interested in the mechanics of newer non-cat stoves and what is supposed to make them such clean and efficient burners.

 

[grommal]

So, is that it? The ceramic baffle and the burn tubes or some sort of perforated metal which jets secondary air into the firebox? And is that the common denominator in non cat EPA stoves?


I'd like other non cat owners to explain their firebox and draft systems and state what makes their EPA stove an EPA stove. After watching this one my camp yet settles in the catalytic field.

My limited understanding says that is it right there. We looked at a lot of stoves before our purchase, and all the non-cat solid fuel stoves had either a plate or tubes up there in the top, with holes for secondary air burning.

There are two main methods of meeting the EPA standards. One is by re-burning the smoke in a catalytic converter, the other is to re-burn it in the baffle burn tube chamber/area. Both are "secondary" combustion.. which cleans up most of the remaining particulates in the exhaust, just with different methods.

There is actually another type of non-cat secondary combustion system. It involves a separate insulated chamber in the rear of the stove where superheated air is introduced to ignite the gases. VC pioneered it, called "everburn", and others have similar designs, e.g. the Lopi Leyden and the Harman Oakwood and TL300.

 

[begreen]

Dakota, I have no problem shutting the stove down. The problem I have is lack of forceful air intake. Most of the time I have to crack the door to start a fire, even with fire starters. If anything I wondered if the draft control was messed up coming forward. But, it opens all the way.

That's not uncommon in weaker draft situations. Lack of air intake = lack of draft sucking the air in. Did a liner get installed?

 

[madrone]

I'm pretty sure the Fusion will do it for you. I'm biased, and not qualified to speak with authority, but I can't figure how a non-cat stove works for a darn without a N/S load. I love my square firebox. The other day I loaded E/W for the first time in a year just for an experiment. It was warmer out, and I keep reading how E/W is great for slowing the burn on warmer days. It sucked. I had a hard time getting it running, and ended up having to open the air more for longer, resulting in a shorter burn. Loaded N/S, I have the thing shut down almost all the way within a half an hour, from a cold stove. Secondaries rolling like a steam train's fire box. Looking at pics of the Homestead, it looks like it's 10 inches deep, (yes, I know it's not). Not for me.

 

[begreen]

I like the flexibility of a deep firebox too. But sometimes I burn E/W too. Usually when I have a bit longer splits. Not a big deal for me really, but 100% of the time my starter fire is N/S. However, I always leave the door open a little until the fire has a good start.

The Castine has a shallow firebox. With good draft it works fine. I don't remember any issues with even burning. Occasionally I'd have to deal with a log rolling up against the glass, but it was not a daily thing or a serious issue.

 

[REF1]

Yes, I installed the liner and added another foot and a half of flue. If draft is a problem it escapes me how, when I do get good hot fires going. It's getting them going that is the problem. But now, with coal beds, it's obviously not a major problem. But yes, when a log rolls against the doghouse and suffocates the fire I want to throw the stove out the back door. The depth of this stove is 12." I will never own a shallow fire box like this again. I have learned my hard lesson. An expensive one, too. If the shallow fire box with E/W loading is part of the efficiency of EPA stoves - keep it. It makes no practical, or theoretical sense to me. Not with the draft system my stove has. The Fusion should be here Monday. I'm looking forward to receiving it and setting it up.

I didn't know there was discussion of E/W vs. N/S loading. I'll have to do a search and see what that's about.

 

[Dave_1]

REF1,

fwiw

To stop logs rolling against the doghouse make the nearest piece to the door a split.

Assuming that your flue has no blockage & or leaks the following ought to help, this is how we start a fire in a pre EPA Fisher.

1.) Take license plate & sweep about half the ash, from front to back, to the left side of the stove.

2.) Next rake the coals out of the ash to the far right side of the stove.

3.) Now you have a clean channel to add 2 pieces of dried kindling, about 12" x 2" x 1", a hand width apart, between the coals & ash.

4.) Next add a handful of pine straw between the 2 kindling pieces & about a dozen pine cones on top of the pine straw.

5.) Install some medium splits that are 12-15% m.c. & one large split on top of the pile.

6.) Lit the pine straw & adjust the air to the stove until the straw goes from a lazy burn to looking like it is being blow torched. :bug:

Try that procedure & let us know how it goes.

Good luck with it. ;-)

 

[REF1]

Interesting start up. In my case ANYTHING falls forward because the draft on this stove, which folks call a 'doghouse," torches a tunnel in the load. No matter what kind of split is on the bottom, it gets basically torched in half, and when it caves, anything on top falls forward. Happens almost every day, every full load. Plus, the design of the firebox contributes, as well. It's small and the roof of the stove is pitched, not flat. So, you can throw one split in the back maybe a large and small next and have the most room right at the door. So, you put a couple good splits there. Sooner or later, the top will fall forward and park right min front of the doghouse. I have found the entire design of this stove to be faulty. I didn't realize it until I noticed from a side view that the smoke has to travel up that pitch, curl through the front exit, then it has to go DOWN somewhat to meet the stoves flue exit. So, smoke travels up the pitch, then down the pitch to get to the flue exit. It's crazy.