Why does EPA require stoves to test under 1 Kg/hr?

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I thought the stoves were warmed up first. Are stoves tested before they warm up? If so, I would think that emissions from a cat stove would be terrible until the bypass is closed.

More mass can help even out overnight temperature swings. Soapstone and cast jacketed stoves seem to do this well. We have woken up with just dwindling coals, but the room temp is still comfortable.
 
"8.11 Pretest Ignition. Build a fire in the wood
heater in accordance with the manufacturer's written
instructions.
8.11.1 Pretest Fuel Charge. Crumpled newspaper
loaded with kindling may be used to help ignite the pretest
fuel. The pretest fuel, used to sustain the fire, shall
meet the same fuel requirements prescribed in Section 7.1.
The pretest fuel charge shall consist of whole 2 × 4's that
are no less than 1/3 the length of the test fuel pieces.
Pieces of 4 × 4 lumber in approximately the same weight
ratio as for the test fuel charge may be added to the
pretest fuel charge."
 
I thought the stoves were warmed up first. Are stoves tested before they warm up? If so, I would think that emissions from a cat stove would be terrible until the bypass is closed.

More mass can help even out overnight temperature swings. Soapstone and cast jacketed stoves seem to do this well. We have woken up with just dwindling coals, but the room temp is still comfortable.

Good Points.
 
I think hairs are getting split way to thin when it comes to wood stoves.
Might just as well outlaw them all(non pellet wood stoves) and make everyone get the fancy hi tech super clean wood burning stove..the pellet stove,seems to me the future of wood burning is already here.
 
Interestingly in New Zealand where they have some very tough new standards and some very clean burning stoves available, they still have a horrendous smoke pollution problem in many communities. In part this is because fireplace burning is not banned and old stoves have not been replaced. And then there is the yahoo who thinks green wood burns better because it burns slower. Their geography traps this smoke during temperature inversions. In communities where rules are strictly enforced they are noting improvement.

smoke_pollution_nz.jpg
 
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I would say from what I see at my job 5% would be a good conservative number and it may be slightly higher.

That 5% would be much higher if it was as simple turning a screw on the back. Stove designs have made it very difficult to manipulate the low burn rate on the stove which is why we must resort to flue controls.

Internal combustion engines are allowed adjustment for things like altitude. Stoves have issues that need the same ability.

When was the last time you bought an engine BB? Even our beloved chainsaws have limiters on the adjustment screws that only allow for very minor variation in fuel/altitude/temperature. The motorcycle I rode today has a carburetor that was very lean from the factory. To adjust the carb jets I had to remove a pressed in plug that was put there to prevent adjustment.

It's been a long time since adjusting a "pollution controlled" device was easy or intended to be done by the user.
 
Right on that Highbeam. The EPA wants it so people can not make wide adjustments to the units. It's all about pollution control. They don't trust the average woodburner enough to allow them that much control. That is why the cat stoves have a limit of 1.4 g/hr they figured into it that so many % of owners wouldn't replace the cat when it wore out so they lowered the limits from the beginning to make up for that. There is not too many aspects of our lives that aren't gov't controlled. NYC doesn't trust people enough to let them buy a 32 oz. coke from McDonald's.
Even on flue dampers they only want them to block a max of 80%. Thus many of the ones you buy now have holes in them or stoppers built in so you can't damp them down 100%
 
It's been a long time since adjusting a "pollution controlled" device was easy or intended to be done by the user.

Yeah but the dealer can make the adjustments. Which is what I said is needed for stoves. Since they don't have closed loop control computers that do the adjusting.

Familiar with pollution controlled engines. Nobody but me has laid a wrench, except for front end alignments, on any of mine since 1973.
 
I've drilled my share of carb jets too. Getting a four stroke gas engine to run properly by tampering with emissions controls is a long running tradition. It's pretty simple and gains in both mpg and power are easy. I've done some tampering with diesels now too which is even easier.

With the cat stove and its manufactured ability to burn low and slow for extended periods I have not felt a need to tamper with anything. Now the hearthstone non-cat, I had that sucker run away on me a few times and would have loved to find an easy way to gain control of the intake air. I find the NC30 much more "snuffable" and it is unmolested. This to point out that some stoves behave better than others while also meeting the low emissions regulations in place.
 
Even on flue dampers they only want them to block a max of 80%. Thus many of the ones you buy now have holes in them or stoppers built in so you can't damp them down 100%
I can not think of many circumstances where one would ever want to block off a flue 100%. If one did, where would the flue gases go?
 
I can not think of many circumstances where one would ever want to block off a flue 100%. If one did, where would the flue gases go?
Chimney fire would be the only thing I could think of.
 
Count me in that 5%.. with 26 feet of triple wall chimney in an enclosed chase, I had to make and instal some sliders for the bottom of my stove to be able to slow down the secondary intake air. Otherwise I would run through a full load in 4 hours and it would be gates of you know where for most of it. I have my intakes blocked about 40% most of the time.
 
The 1.15 kg/hr issue is part of a much larger topic. The EPA has proposed a two-stage reduction to the current emissions limits. Stage 1 would set the limit at 4.5 grams/hr, and Stage 2 would further reduce it to 2.5 grams/hr (the possibility for a Stage 3 limit of 1.3 grams/hr has even been mentioned). On top of that, the proposed legislation would specify cordwood, not the current nailed-together dimensional pine "cribs," as the test fuel. The HPBA is concerned that the majority of today's models, particularly non-catalytic models (which comprise 83% of today's marketplace), would not meet Stage 2 standards burning cordwood at a low burn rate of 1 kg/hr, and is proposing a slight increase in low-setting combustion airflow to 1.15 kg/hr. If the EPA accepts, the responsibility for the increased airflow won't be left to the end user: draft control modification will be accomplished at the factory, and all Stage 1 stoves will ship with a slightly higher low limit.

Until the Stage 2 deadline, that is. Industry sources indicate that a 2.5 grams/hr limit would create the need for prohibitively costly modifications to today's designs, and most likely eliminate the non-cat option altogether. The HPBA, working with Republican members of the House of Representatives, has created House Bill HR 4407, which would require the EPA to take a more reasonable approach. The next step is to line up Democratic sponsors, which will be critical if the bill is to pass.
 
I have noticed a movement for one standard for all stoves. There is a petition on Woodstock stove website
 
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