*Outdoor Wood Boiler Complaints*
How Visibly Smokey Are They?
By: Jaden
09 October 2006

Classic Boiler CL5036


How much you wanna bet some oil company(s) have their fingers in to this? Possibly the goobermint too because they're losing tax $$ by reducing oil sales. I can come up with 6 different taxes they're losing right off the top of my head.

There was an article in the newspaper recently entitled "Smoke gets in your lungs". It was written by the CEO of the American Lung Association of Maine & a physician who is a member of the association's board of directors.

Apparently the "American Lung Association of Maine" has identified outdoor wood boilers as a *serious* lung health hazard requiring immediate action.

The article talks about air pollution being a significant problem in Maine and a serious health risk, especially for more than 150,000 ppl with lung disease. (How much you wanna bet that over 3/4 of that # are or were smokers or that it was caused by breathing 2nd hand cigarette smoke?) Kinda made me wonder.

They continue on to say: "It's time to demand that outdoor wood boilers be made to meet EPA emission standards like all other wood stoves." (Umm....woodstoves are a pretty simple device. The wood burns and the smoke exits through the chimney. There's no smoke purification on wood stoves) A boiler is nothing more than an oversized wood stove. I've seen hundreds and hundreds of wood stoves and have never seen one with EPA standards on it. Maybe I've just overlooked it every time. Next time I see a new one for sale, I'll look to see if it has an EPA emission standards rating. So read the above quote again carefully. UPDATE: Iíve looked at stoves at two different stores and havenít seen EPA standards on them.

Continuing: "At first outdoor wood boilers might sound like a sensible and benign way to heat a home, but they are actually dangerous polluters. The average wood boiler emits over 70 grams of particle pollution per hour, that's over 15 times the EPA standard for other wood stoves"...No chit Sherlock....It's 15 times bigger than a "normal" woodstove. DUH!! Yea, it's a sensible way to heat my home because I live in the sticks and wood is easy to come by. FREE!! It's hard for the average Joe here to heat their house using propane/fuel oil, especially with these outrageous prices.

Notice above that the quote said "average" wood boiler. They donít state what they constitute as "average". In the quote before that they says that "itís time to demand that outdoor wood boilers be made to meet EPAÖblah blah. OkÖ??Ö.what about companies that already build a quality boiler? IMO, the message the article is trying to project is that ALL boilers are dangerous pollutersÖthatís the impression I got when reading it. They donít state what brands of boilers are "average", they only say that wood boilers are dangerous polluters. Notice the flip-flop & inconsistencies there.

Lest we forget that the US Forest Service endorses burning wood....something not adding up here?? Check out the link below to central boiler. Then click on environmental advantages.

Here's a quote off my brochure for my Central Boiler. "Wood is a totally renewable resource and when burned, results in no net increases in carbon dioxide. On the other hand, fossil fuels when burned release carbon dioxide, which would otherwise be trapped in the earth. The burning of fossil fuels causes a net increase in carbon dioxide which is believed to be responsible for the heat trapping greenhouse effect"

OK....It gets better now :o)

Continuing from the newspaper: They are large enough to burn trash, demolition waste and other dirty fuels unsuitable for residential combustion....yea, so what? Read the PLACARDS on the boiler, it tells you not to burn anything but CLEAN wood, that's also stated SEVERAL times in the owner's manual. (Look at the top picture right by the door handle. That sticker warns not to incinerate trash) Burning trash and wood with chemicals will screw up the integrity of the boiler. Nothing (except for the Facta Non Verba below) but clean dry wood goes through MY boiler door!! Follow the directions and cautions and what's the problem again? I've seen people burn pressure treated wood/plywood/chipboard in a wood stove INSIDE of their house!!!

It goes on to keep bashing boilers by comparing them to heavy-duty diesel trucks. "Imagine having 2 heavy duty diesel trucks idling in your back yard. That's the same as operating an outdoor wood boiler." Uhh...nooo....diesel is fossil fuel that burns in an internal combustion engine....wood isn't. How is that the same??? I also don't think wood boilers are quite as noisy as 2 idling diesels.

The biggest complaint I can see in this article is the visible smoke. Well...I happen to know some people who have boilers and burn WET and GREEN wood in them. Heating water until it turns in to a gaseous state creates what?? STEAM!! So somebody burning wet/green wood in a boiler will be generating smoke, but all the sizzling that's heard is the moisture converting to gas. Then it's STEAM and it exists the chimney along with the smoke. Burn the same wood in a wood stove that "meets EPA standards" and you'll get the same result. Burn the same wood for a campfire and you'll get the same results. IMO Wood boilers do NOT cause this problem. So is it unhealthy to breathe steam? Better be careful the next time you're around a hot tub or take a steamy shower. You'll be polluting your lungs :o)

Seasoned dry wood burns pretty clean meaning it produces little smoke.

Continuing: "The American Lung Association of Maine believes that burning wood does not have to be a threat to your health. It is a safe and renewable resource that is safe and efficient when burned properly." Define "properly". They fail to do that. How do you make clean wood burn properly? They talk about normal wood stoves burning at a higher temperature than boilers. Ummm.....to my knowledge, wood combusts at a certain temperature regardless if it's in a boiler, wood stove, campfire or even a structure. Wood is wood. Yea, when a house isn't calling for heat the wood sits in the boiler and smolders,...(yes it will be at a lower temperate at this point until the house needs heat or the jacket water temperature drops below the preset temperate (a nice feature on the Classic Boilers) then the fire is ignited) when the house wants heat a draft is created and the wood comes up to temperature and heats the water. There'll be a big puff of smoke as the wood ignites. My boiler will maintain a jacket water temperature of 185 degrees F whether the house wants heat or not.

I might be wrong, but it seems to me that *somebody(s)* wants to railroad the wood boiler industry. Their comparisons to diesel trucks in the back yard and all of the other negativity would most likely discourage the "average person" from buying an outdoor boiler.


I wonder if the authors mentioned above have actually tested various wood boilers with different types of wood. Iíll admit, Iíve seen this Taylor boiler producing a lot of smoke, HOWEVER I know the owner was picking up scraps off the ground from a wood yard during the winter, therefore it was wet. The chimney on this Taylor is short; it terminates just above the top of the picture. It also doesnít create itís own draft; it needs a fan to create a positive pressure in the firebox.

Ok, Iím going to FNV this newspaper article using my Classic CL-5036. Letís see how much smoke it produces. Granted I donít have any way to test for grams of particulate pollution, but letís do a visible smoke test.

With a firebox full of old barn boards and scrap wood (clean stuff, no paint or chemicals) it produced a lot of smoke.

Boards----------------------------------------smoke produced

Once the boards burned down, I threw in a bunch of DRY stumpsÖkey word DRY!! With the stumps blazing this is the amount of smoke produced


Stumps ablaze-----------------------------------Smoke produced

The jacket water came up to temperature and the draft door closed. This caused the stumps to sit in there and smolder.


Stumps smoldering---------------------------------smoke produced

After I managed to get the jacket water temp down, the draft door opened and the stumps ignited (after smoldering for over an hour). There was a short puff of smoke and then it looked like the picture above. Still havenít seen anything that looks like two heavy-duty diesel trucks and this boiler sure isnít as noisy as even 1 diesel engine!! Pretty much have blown the authorís comment about wood boilers being the same as two diesels out of the water.

I have seen chimneys with the same amount of smoke, if not more bellowing from them.

I threw in some green pieces of maple & poplar that I cut last week, theyíre sizzling but thereís still not much smoke. Probably if I stuffed the firebox full of green wood, thereíd be a lot more steam.

So my conclusion is, using my CL-5036, if you burn dry clean wood the smoke is visibly no different and in no greater quantity than an ordinary wood stove that "meets EPA standards". On occasion there would be a downdraft and push the smoke down toward the ground, but that happens with ordinary stoves too. The only real advantage I see to an ordinary wood stove, is having a chimney that exits through the roof, usually 30í or so above the ground so the smoke has more of a chance to blow away. The Classic boilers can have as much chimney added as necessary to accomplish the same. Mine is about 20í above the ground and seems to be working just fine. The Taylorís chimney pictured above exits maybe 8í above the ground. So yea, it can easily fill a dooryard full of smoke and be a nuisance. Get the chimney up in the air a bit, burn dry clean wood, donít incinerate garbageÖ.simple.

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