Any clean wood furnaces, 6" flue?

I live in WA and our current rules require 2.5 gph for cat woodburners and 4.5 gph for noncat woodburners. In my shop I have a 6" flue and the biggest wood stove I could find installed and permitted. I am dreaming of a furnace for the additional output, ductability, and automation.

I need a furnace to be legal which means "certified" to meet WA standards as well as able to feed a 6"flue. Anybody have any recommendations?

Did they get an EPA tag? @lampmfg ?

So it seems that most wood furnaces are dirty burning then. Or at least too dirty compared with stoves. That's too bad and I hope the coming epa regulation will clean them up like it did with stoves.

velvetfoot said:

How did you come up with that conclusion? Gasification produces a clean burn. It costs money to get EPA certification and puts a strain on a small company.

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I asked. Do you know of any?

STIHLY DAN said:

Yes, #1 Kuuma, #2 psg caddy, #3 tundra. My furnace burns cleaner than most stoves. The EPA regs have just about started for furnaces. The 3 above have already had the testing (big money) its just a paper work thing with the government now. Have you put in any effort to find out, other than asking?

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I have and none of those work. Certified to 4.5 gph or less and 6" flue.

Kuuma not certified, caddy and tundra both are 6.6 gph but certified.

6.6 gph is silly dirty. It could just be a different testing protocol vs. stoves but to be legal in Washington we need 4.5.

STIHLY DAN said:

So Washington needs epa certified, or Washington state certification? The Epa Tag I don't think has started yet, Is the interteck testing results not good enough for Washington? If Washington has its own special certification I would think that would be low on the manufacturers priority list. Sorry for the ignorance but I have no idea how your states rules operate. These are honest questions, not wise cracks or know it all remarks.

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The way I read the law is that all wood burners must be EPA certified AND meet WA's stricter emission standards. So you can be EPA certified but still not clean enough for WA. That appears to be the situation that the caddy and tundra are in.

Here's the actual WA law

"After January 1, 1995, no solid fuel burning device shall be offered for sale in this state to residents of this state that does not meet the following particulate air contaminant emission standards under the test methodology of the United States environmental protection agency in effect on January 1, 1991, or an equivalent standard under any test methodology adopted by the United States environmental protection agency subsequent to such date: (i) Two and one-half grams per hour for catalytic woodstoves; and (ii) four and one-half grams per hour for all other solid fuel burning devices. For purposes of this subsection, "equivalent" shall mean the emissions limits specified in this subsection multiplied by a statistically reliable conversion factor determined by the department that compares the difference between the emission test methodology established by the United States environmental protection agency prior to May 15, 1991, with the test methodology adopted subsequently by the agency. Subsection (a) of this subsection does not apply to fireplaces."

They, WA, allow some pellet boilers and furnaces that apparently pass some version of EPA certification as well as the lower 4.5 gph rate.

I expect that once the kuuma becomes EPA certified at less than 1 gph that we will have the first legal wood furnace available for WA. The price of a Kuuma is very high. Though they sound like great furnace.

Does anybody know of any other sub 4.5 gph wood furnaces for a 6" flue? Even those that have not yet been certified but may be in the future?

David_QC said:

City of Montreal (Quebec, Canada) are thinking about restriction like Washington,
See article:

http://www.cbc.ca/news/canada/montr...ces-could-face-restrictions-by-2016-1.3017685

I think they should add a restriction for wood buying/selling that are more than x% of moisture, that would make more sense as the gph of certified furnace are with top quality wood...

There is a few furnace/woodstove manufacturer in Quebec, that rule could speed up the quantity of certified furnace in the near futur.

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There is already a wa state law that requires 20% or less moisture content on our firewood. I was surprised to see that one.

brenndatomu said:

Bam! <4.5 GPH Washington State certified (per their site)
http://www.drolet.ca/en/products/wood/furnaces/extra-large

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Cool! A lot of people have been waiting for this big brother to the heatmax. 4.9 c.f. I couldn't find the gph emissions rate but saw the 78.9% efficiency which isn't too bad right?

brenndatomu said:

Not too bad I 'spose, right in that 80% range that most of 'em claim
"Average particulate emissions rate : 0.735 lb/mmBTU (0.316 g/MJ)"
The EPA and Washington state label is right below the picture on the Heatpros homepage

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I read that too but they do not provide the emissions rate in gph which is what washington requires to be below 4.5.

brenndatomu said:

I dunno, I just seen the "EPA and Washington State certified < 4.5 GPH" label and figured that means they will be legally sold there...

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I hope so. Without the actual gph emissions rate it is still illegal. We don't know price yet and with drolets cracking heatmax history it will be good to wait a bit. By then let's hope that other, proven stoves like the kuuma gain approval.