Switching to an EPA stove?

[Whitespider]

For any of y'all thinking about, or in the process of, switching from an older type fire box with a grate in the bottom to one of the new-fangled, glass door, no bottom grate, secondary burn, EPA type fireboxes...
Well... I've learned a few things I'll pass on so ya' don't have to waste time learnin' the hard way.

1. The most important thing is they like fully-seasoned, dry firewood... they hate damp, wet or under-seasoned firewood
2. The second most important thing is they like fully-seasoned, dry firewood... they hate damp, wet or under-seasoned firewood
3. You need to start splitting just a bit smaller than you have been... I'm now splitting about three-quarter the size I was
4. Don't wait until the house is cold to start the fire... they (or mine) will take a good hour or better to come fully up to temperature
5. Filling the firebox by "fitting" splits tightly together (like puzzles pieces) makes the fire slow to get going... which means even longer for #4
6. The fire is never totally out... sticking your bare fingers into (what you think is) a cold ash bed will result in a nasty burn from very hot coals down in there
7. Closing down the draft too soon (like before the secondary burn kicks in) will likely result in a firebox that never comes up to temperature
8. Don't expect long (all night) "heating" times... but hot coals are another thing (see #6)
9. It is entirely possible to heat yourself clean out'a the house if'n ya' reload one to many times during the day

 

[mellow]

Most of these items you should have been doing in a pre-epa stove.

 

[Dalmatian90]

The fire is never totally out...

*snork*...in my POS Boxwood stove I through a pizza box yesterday morning to get it off the counter. Had a short warm spell so no wood had gone on the stove for about 36 hours IIRC.

When I came home from work and went to load up the stove...no more pizza box. Discounting the possibility of really determined squirrels, it would appear I had some embers left

 

[CTYank]

Some "EPA" stoves like my little Morso Squirrel have a grate and ash box below.
Helps to get things going, with the door cracked a mite.
One part of the grate can be rotated from the outside, to send some ashes into the drawer.

On startup, I just watch the thermometer on the flue nearby. 250F or above, OK to close door
Oh yeah, almost forgot. Wood cannot be too dry. Ever.

 

[dave_376]

A lot of what you are seeing is that your system of stacking wood outdoors and never coverering it does not get it as dry as wood stored in a proper woodshed. I can place properly seasoned ten inch round on a bed of coals and get into secondary combustion mode in minutes and stay in that mode until the round has collapsed into a bed of coals ten to twelve house later.

Hang in there......you're catching on!

I wish more people would clarify things like this. I listened to the people that said "not to cover because it will dry better/faster".....NOt true as I am now finding out. My wood is slightly damp and I'm forced to do what I didn't want to do, bring lots of wood in the house.

Next thing on the list build a wood shed.

 

[Dalmatian90]

No, firewood is not supposed to dry.

It's supposed to be dry to burn well and/or more safely in "modern" woodstoves -- starting with the airtight Fishers and later the EPA stoves.

And there are some good advantages to it in those circumstances. And good reasons to use those stoves.

But for most of the time we've burned wood, folks have burned unseasoned wood.

Do you think back when the Civilian Conservation Corps built camps across the country they went out and found seasoned supplies of firewood?

Of course not, they burned what the CCC boys cut that year. Matter fact, the last two show stoves basically identical to what I use today.

It's also not the moisture in the wood that robs BTUs. Red Oak loses 1500# in the process of seasoning, has 27M BTUs in that cord. It takes 1100 BTUs to boil off one pound of water -- 1500 * 1100 = 1.65M BTUs or only about 1/8th of the energy in that cord. Trivial.

The real losses come from the amount of air the older types of woodstoves shove up the chimney. That's probably 50% or more of the heat, vs. 15% difference whether it's seasoned or not.

With the introduction of Fisher stoves the air flow was reduced, but creosote was a big problem especially if the wood wasn't seasoned because of the amount of condensation that formed in the chimneys now that the smoke wasn't being exhausted as fast. EPA stoves improved on the air-tightness by adding catalysts or secondary burn to now burn that fuel in the smoke that used to get shoved up the chimney.

I heat my house just fine on damp, wet, and unseasoned firewood, just a lot of it. One day I'll put in an EPA stove and will need dry, seasoned wood supply...but only half as much.

 

[Ductape]

*snork*...in my POS Boxwood stove I through a pizza box yesterday morning to get it off the counter. Had a short warm spell so no wood had gone on the stove for about 36 hours IIRC.

When I came home from work and went to load up the stove...no more pizza box. Discounting the possibility of really determined squirrels, it would appear I had some embers left

Pepperoni ?? :msp_confused:

 

[Arbonaut]

Thanks for the heads up.

 

[Whitespider]

A lot of what you are seeing is that your system of stacking wood outdoors and never coverering it does not get it as dry as wood stored in a proper woodshed.

Nope, not true Del.
The wood from my two-year-old stacks is bone dry and burn very well. The experience I've had with damp,wet wood has been from the bottom 10 feet or so of standing-dead I've just recently cut, split and tossed directly in the firebox. If I stack the damp, wet standing-dead in the basement for about 10 days or so it also burns just fine.

The reason for the smaller splits is because the firebox is smaller... not because it won't burn. I can get more wood in the firebox using smaller splits... especially when topping off the fuel load before bed.

I've tried several different things, ain't no way all that firebrick and the sides/back of the stove come up to full temperature in 20 minutes. It flat takes time for all that brick to sync heat before it transfers it to the steel sides. Remember, I'm using my firebox in a forced-air plenum... until the sides and back get as hot as the top (which heats up darn fast, by-the-way) the forced-air won't pick-up near as much heat.

Tossing wood on a bed of coals is not what I was posting about... my observations are from a cold start. Sure, I easily have a bed of coals after 10 hours, even 20 hours. But they ain't making a lot of heat, barely hot enough to keep the sensor engaging the blower after 6-7 hours. I get 4-5 hours of real good heat coming from the vents and then it rapidly tapers off.

The old steel smoke dragon would start throwing good heat in just 10 minutes or so... and keep throwing constant good heat until the bed of coal was near burned out. I could easily get a good 10-12 hours of constant, solid heat from it... but I could also get 3 times the wood stuffed in it. The "problem" with this new EPA firebox is that it burns directly on the firebrick and no air can get under the coals to keep them screaming hot. I have no use for a "warm" firebox... I want a "hot" firebox. Once this new firebox comes up to temp it throws more heat than the old one... but it takes longer to get there and don't last near as long. So far, I remain unconvinced that this is necessarily a more "efficient" way to burn wood. I guess it depends on how you define "efficient"... and I think a ton of heating potential is lost buy not feeding air under under the fire (coal bed). Also, once the fire collapses into coals there is still air being fed through the upper secondary baffle... which only serves to further "cool" the fire box.

 

[stihly dan]

Also depends on the make of EPA stove. Not all stoves are the same. There is a huge difference in performance, and ease of use.

 

[Arbonaut]

If you lived 1500 miles farther South, Whitespider like in Bartow County Georgia, it would be realistic to get the same bang for your input with that EPA job as you'd like now. However it got 24 Degrees here last night and losing ground temp fast. You up there, gonna hafta scrap the Greenie Wacko rendition of what wood heat is and get real. You're a down to Earth guy and got a grasp of physics. Greenies got their head in space.

Pair up your system with what you are trying to accomplish. You want a good burn, it takes oxygen. Sorry about cheating the polar bear; one less to eat me in a pinch, that's the bright side.

 

[trophyhunter]

I find that I changed my splitting habits to include some smaller pieces for epa stoves due to reduced firebox size. By having a good supply of smaller splits in the mix I can top off larger 6-8" splits and actually get the stove full of wood.

It helps for the overnight loading at any rate and I like to rake all the charcoal to the front of the stove and place one very small split on top to get that burned down once a day.

 

[Whitespider]

I wish more people would clarify things like this. I listened to the people that said "not to cover because it will dry better/faster".....NOt true as I am now finding out. My wood is slightly damp and I'm forced to do what I didn't want to do, bring lots of wood in the house.
Next thing on the list build a wood shed.

My stacked uncovered wood is pop-corn-fart dry... and it just rained all day on Sunday.

 

[Whitespider]

You up there, gonna hafta scrap the Greenie Wacko rendition of what wood heat is and get real. You're a down to Earth guy and got a grasp of physics.

Yeah... I'm seeing some serious Spidey modifications to that firebox in the near future.

 

[iowa]

May I ask what stove or furnace this is. Perhaps its not a very good design?

 

[ancy]

Yeah... I'm seeing some serious Spidey modifications to that firebox in the near future.

Take the fire brick out and put a grate in before you go cutting the air tubes out. I can heat my 1500sqft x 2 ranch easily and it's in the garage....

Sent from my XT881

 

[gregfox]

Bone dry warm wood is one of the most important parts of my EPA stove. The second is the shape of pieces you're feeding it. Mine likes 2-3"X6-8" flat pieces stacked to fill the box, maybe a couple smaller under it pending coals. All those triangle shaped pieces may be more efficient to split, but just don't maximize(or do the job) for my stove. It'll take some time to learn your new stove.

 

[Whitespider]

May I ask what stove or furnace this is. Perhaps its not a very good design?

The firebox is a Pacific Energy Super Series Spectrum... I removed the fancy porcelain coated trim panels from the top and sides, built a forced air plenum around it and installed it sort'a like an add-on furnace. To limit heat loss through the clear ceramic panel in the door I built an aluminum reflector that hangs in front of it... that has worked well, allowing me to run the fire box at lower settings and gain burn/heating time.

This isn't anything I haven't done before, although I've never used an "EPA" firebox as the foundation. My complaint isn't that it won't heat... it heats the whole house just fine when it's heating (actually throws the best heat of any I've built).
My complaints are;

1. The length of time required for the complete firebox to come up to full temperature from a cold start. I got out'a bed at 5:00 AM, the house was 64[sup]o[/sup] (not uncommon this time of year because we haven't had the fire going since yesterday morning). It is now 6:00 AM, the fire has been burning for 45 minutes (actually roaring good right now) and still very little heat from the vents... because the sides and back have not come up to temperature yet. And the house has now dropped to 63[sup]o[/sup]. It will likely be another half hour before the whole firebox (fire brick) heats up and it starts throwing good heat.
2. The relatively short length of peak heating time. There's a very simple reason for this... the main fire isn't "efficiently" fed an air supply (because no air can get under it when burning directly on the firebrick floor) and once the secondary burn shuts down heat output is drastically reduced. And, the air still being fed to the "secondary" is simply helping to "cool" the top part of the firebox. At peak, I'd much rather have a little less temperature that lasted longer.
3. The extremely inefficient use of the coal bed. When I can find smoldering coals and embers on the floor of the firebox some 30 or more hours after a fire... that's a waste of heating potential. If the fire was up off the floor on a grate, and air was fed under it, a deep coal bed becomes an extremely "efficient" source of heat (they burn screamin' hot until completely consumed into ash). The way this (so-called) "efficient" EPA firebox works will be a huge PITA when temps drop below zero because the fire will need to be "heating" through several fuel loads... and with no air getting to the underside, the coal bed will just get deeper and deeper, while producing relatively little heat and reducing the firebox capacity. And again, the air still being fed through the secondary just "cools" the top part of the firebox.

It has taken me awhile to type this because I go refill my coffee cup, step out for a smoke... it's now 6:50 AM, the fire has been going strong for near an hour and a half, finally getting really good heat and the house temp is 65[sup]o[/sup]. So, two hours after starting the fire, and actually losing ground waiting for it to come up to temp, I've managed to gain 1[sup]o[/sup] since getting out'a bed... and it's above freezing out side! Admittedly the house temp will rise rapidly from here on; but the old smoke dragon would have had the house up around 70[sup]o[/sup] an hour ago... then I could have choked it down about now, and taken advantage of the coal bed to maintain that temp until midday (when it would go completely out after actually using all the heating potential of the fuel load).

So far, I'm not overly impressed.
I'm thinking the advantages of this (so-called) "efficient" EPA firebox are far out-weighed by the advantages of the old smoke dragon... and the word "efficient" isn't what I would use to describe the EPA advantages.

 

[Whitespider]

Take the fire brick out and put a grate in before you go cutting the air tubes out.

That's probably gonna' be the plan; at least removing the brick on the floor, install a grate, and try that first... maybe put the main and secondary air supplies on separate controls. It doesn't exactly have "air tubes", it's a removable top baffle with a single air supply channel at the rear of the firebox feeding it.

 

[Whitespider]

You bring a lot of misconceptions to wood heat. One of them is that a wood fire should be fed air from below a grate in the bottom of the stove. That's how coal is burnt, but not wood. I have a grate in the bottom of my Jotul Firelight but if I fed combustion air up through the grate for more than a brief period at start up, and it's not recomended, it would destroy the stove.

Whatever... misconceptions my achin' butt.
Every other firebox I've ever had (over a dozen) fed air under a grate... every single one! Even my homemade barrel stoves had a grate of some sort installed.
Every firebox my dad has ever had (more than me), including his current one, fed air under a grate... every single one! He even put a fireplace grate in the barrel stove "kit" he had in his shop at one time... because it dramatically increased "efficiency"!
The difference between burning coal and burning wood on a grate is how much air you feed it... (well, there is the "shaking" and "banking" of the coke also).