Insight video report concerning OWBs.

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Gentlemen,

Emission and efficiency results can be improved with lambda control and a simple run time hour meter. While neither of these technological add-ons can completely fix operation with poor fuels or bad techniques, they give ample feedback to the user so that shortcomings can be realized more easily. Until I had an hour meter for instance, I had no idea how severely over-sized my boiler was for my house and 500 gallons of storage. The boiler was entering slumber long after I lighted it and had gone to bed. In the morning, the boiler had burned out cleanly and there was no evidence of slumber. After seeing hours of run vs. hours of slumber, I put in a smaller boiler. Here is how the lambda control helps: Wet wood will generally result in higher oxygen readings and low stack temperatures. Some boilers will simply shut off when thresholds for those measurements are reached. A careless operator will likely learn best practice more quickly when their machine will not cooperate with improper use. Of course lambda control also cleans up even normal and good operation, but it really can help educate a lazy, naïve, or ignorant operator.

On another note that has come up in this string, the thing that a lot of people don't talk about is that EPA is not currently going to begin the NSPS with a single test method that allows comparability across all wood burning boilers (OWB, IWB, HH or whatever one may call it) and better yet, all wood burning devices. At the moment, I understand that a consumer may be faced with up to three different methods for wood boilers with very poor comparability across the methods. While EPA compliance will be a good thing, the consumer will be left with many questions about what to buy if trying to compare across models with different test methods. For the benefit of the consumer and wood burning in general, I would like to see all of the confusing data be put to rest with a single, reliable test method.

A Froling FHG (that we loaned NYSERDA) was used to help develop the new Brookhaven test method for boilers with remote thermal storage. Having been updated as to the test method from time to time, I find the method to be sound, fair, accurate, honest and somewhat more expedient than Method 28 or ASTM2618. In fact, I think the method while being expedient, most accurately portrays normal use compared to all other current methods. However, The method is still not one that can be used with boilers that are not connected to remote thermal storage.
 
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After seeing hours of run vs. hours of slumber, I put in a smaller boiler.

I think I would have put in more storage.

And I am quite doubtful that lambda controls can help burn wet wood much better than non-lambda.

IMHO.
 
My humble opinion only, for what it's worth........Thermal storage should be part and parcel to every wood boiler installation. Every wood boiler will run better with adequate storage.
 
Thermal storage should be part and parcel to every wood boiler installation.

Bingo. Want to burn clean & efficient this is step 2 right after seasoned fuel as step 1. Can't for the life of me understand why we don't learn from our cousin's across the pond. Heck they teach for free all we have to do is listen.
 
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I'm a diesel mechanic and so I try to relate everything to vehicles somehow. Having a wood burning device burning clean requires a certain air/fuel mixture just like a internal combustion engine. But when you choke off the air on a wood burner and it still has the same amount of fuel in it, it will burn dirty and inefficient. Just like a Diesel engine, have you ever seen a truck run with a clogged air filter? The injection pump is still giving the same amount of fuel to the engine but the air is severely restricted cause the truck to blow black smoke which is un-burnt fuel. So it's not the storage the makes the unit burn clean, the storage allows it to burn clean at the correct air/fuel mixture through the entire load of wood by having a large amount of water to heat up.
 
Gentlemen,

Emission and efficiency results can be improved with lambda control and a simple run time hour meter. While neither of these technological add-ons can completely fix operation with poor fuels or bad techniques, they give ample feedback to the user so that shortcomings can be realized more easily. Until I had an hour meter for instance, I had no idea how severely over-sized my boiler was for my house and 500 gallons of storage. The boiler was entering slumber long after I lighted it and had gone to bed. In the morning, the boiler had burned out cleanly and there was no evidence of slumber. After seeing hours of run vs. hours of slumber, I put in a smaller boiler. Here is how the lambda control helps: Wet wood will generally result in higher oxygen readings and low stack temperatures. Some boilers will simply shut off when thresholds for those measurements are reached. A careless operator will likely learn best practice more quickly when their machine will not cooperate with improper use. Of course lambda control also cleans up even normal and good operation, but it really can help educate a lazy, naïve, or ignorant operator.

On another note that has come up in this string, the thing that a lot of people don't talk about is that EPA is not currently going to begin the NSPS with a single test method that allows comparability across all wood burning boilers (OWB, IWB, HH or whatever one may call it) and better yet, all wood burning devices. At the moment, I understand that a consumer may be faced with up to three different methods for wood boilers with very poor comparability across the methods. While EPA compliance will be a good thing, the consumer will be left with many questions about what to buy if trying to compare across models with different test methods. For the benefit of the consumer and wood burning in general, I would like to see all of the confusing data be put to rest with a single, reliable test method.

A Froling FHG (that we loaned NYSERDA) was used to help develop the new Brookhaven test method for boilers with remote thermal storage. Having been updated as to the test method from time to time, I find the method to be sound, fair, accurate, honest and somewhat more expedient than Method 28 or ASTM2618. In fact, I think the method while being expedient, most accurately portrays normal use compared to all other current methods. However, The method is still not one that can be used with boilers that are not connected to remote thermal storage.
I agree that in its entirety it wouldn't fit, but there are a few procedures within the method that would strengthen WHH especially the cold-to-cold test bed to account for startup emissions. You also correctly hit on the most important negative issue surrounding cycling technology and that's oversized boilers. As I stated in an earlier post, with the average size Phase II boiler having a 175K output and the average home only needing 40K of heat, it compounds the problem. As Webbie pointed out greed has driven the OWB industry to this point and as a consequence an Army of people are now fighting the manufacturers. Unfortunately, traditional wood burners have suffered collateral damage because of this greed. ( the video bears this out) Essentially what we see now is a patch work of regulation already implemented or on the drawing board to stuff the leaking emission holes generated from OWBs without thermal storage. There are just too many variables that cannot be controlled that effect the technology and even the most conscious operator cannot keep the unit from cycling.
 
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Found this surfing NYSERDA website. Pretty good information in the report, percentage of volatile gas fuel vs charcoal in cordwood (67% to 33%), effects of excess H2O and excess air on combustion efficiency (some, but not huge imo).

They come done pretty solidly in favor of downdraft gasifiers, what they call two stage underfire burners. TTT, time turbulence, and temperaure. They show combustion temp has to be at or above 1200 to 1300 F to reduce CO and C in the flue gas to minimal levels.

http://www.nyserda.ny.gov/Publicati..._european_wood_heating_technology_survey.ashx
 
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