If one were to recomend checking out clean burning stoves to the BI moderator

[elkimmeg]

Here is the testing proccdure Craig asked me to ptoduce

EPA Wood Stove Certification Data Sheet

The testing of wood stoves for EPA certification conducted by Intertek is done following EPA Methods 28 and 5G-3. Below is a short description of terms and procedures.

The emissions rate is the weight of particulates emitted into the flue gas over a given period.

The weighted average emission rate balances the emissions according to the burn rate of the wood.

Catalytic stoves must have a weighed emissions rate of 4.1 grams per hour or less, while non-catalytic stoves must have a weighted emission rate of 7.5 grams per hour.

The stove is tested at 4 different burn rates:
Category 1 = Less than .8 kg/hr; Less than 1 kg/hr if the control is in the full closed position
(Dry wood burn rates = amount of wood minus the moisture content divided by time burned)
Category 2 = .8 kg/hr – 1.25 kg/hr
Category 3 = 1.25 kg – 1.9 kg/hr
Category 4 = 1.9 kg/hr or more (all controls on the unit must be at its highest burn rate position)

The fan is run on high for all runs unless specified differently in the owner’s manual.

Optional fans require another run category with the fan off.

The unit is placed on a platform scale. Single wall pipe is installed to 8’6”± 6” above the scale platform with insulated chimney extending it to 15’± 1’.

The firebox volume is calculated using your production drawings. The calculated volume multiplied by 7 is the test fuel load weight (± 10%). Air-dried Douglas Fir with moisture content between 19 and 25% (dry basis) is cut to 5/6 the largest length of the firebox.

If the firebox volume is:
<1.5 cu. ft. use all 2x4’s
1.5 to 3 cu. ft. use half the weight in 2x4’s and the rest 4x4’s
>3 cu. ft. use all 4x4’s

Douglas Fir spacers (3/4” x 1-1/2” x 5”) are placed at the ends (top and bottom) of test load pieces.

A fire is started with kindling and paper. A preload consisting of 2x4’s at least 1/3 the length of the test load pieces and roughly the weight of the test load is then placed in the stove. The air controls may be adjusted, the door open or the coal bed raked during the preburn. At least 1 hour before the test load is inserted the air controls may not be adjusted. The coal bed may be stirred at any time until 15 minutes before the test run. During the last 15 minutes of the preburn the door can only be open for 1 minute to rake the coal bed.

The test load is inserted when the weight of preload in the stove is 20 to 25% of the test load weight. The scale is adjusted so that the weight is at 0 pounds. The test load is then loaded in the stove within 1 minute. During the first 5 minutes of the test the air controls, fan, and door may be adjusted according to the manufacturers written instructions. After 5 minutes nothing can be adjusted until the end of the test is reached. This occurs when the weight of the wood has returned to 0 pounds. (One stir is allowed after 60% of the test load has burned and the test load weight has not changed .1 pound or 1% of the test load over a 10-minute period, but the door may be open only for 15 seconds during the stir).

Continuously during the test a portion of the flue gas is pulled through a filter collection system. Every 10 minutes a reading is taken of CO, CO2, O2, stove temperatures (the average of the five firebox surface temperatures may only vary ± 125 degrees between the start and finish of the test), gas sample rates, tunnel velocity, stack temperature, tunnel temperatures and dry gas meter readings. These readings provide the proportional flow rate between the tunnel and the collection system. This data is also used for the calculation of the efficiency of the unit following CSA Standard B415. The final grams per hour are calculated after weighing the filters.

 

[webbie]

So who actually burns 2x4's of fir in their stoves?
Or who thinks that burning hardwood rounds will relate to this in a perfect way?

That is my point - NOT whether or not we know what the test standard is, but that when we see it we KNOW that it has little to do with the way the average person uses their stove. Talk to folks who test stoves and they will tell you that you can do the exact same test a number of times on the same stove and get different results! Why? The answer is quite simple to anyone who has burned wood!

Improvements are always being made. If BI is really interested in the most recent technology and the clean results, they should check out the Libby Montana change-out program....
(broken link removed to http://www.woodstovechangeout.org/index.php?id=27)

and contact John Crouch, HPBA government affairs rep.
The libby CO is the most recent, and I think the data will beat the last tests by quite a margin.

After all is said and done, I doubt the BI people are interested in the truth.....maybe I'm a pessimist, but usually folks like this don't change their stripes....but who knows, maybe Elk can woo her!

 

[jjbaer]

Regarding clean burning comparisons, I think folks are mislead and perhaps misleading others to start quoting and comparing these GPH specs as some kid of a sales point. I thought we went over this all years ago - that the EPA testing in no way simulates real world burning AND that it is very possible that certain stoves which are highly tuned for low GPH may not be user-friendly in the field.

Elk, if I may say so, I think this is bad advice to be giving to folks in general. It is not the right way to shop for a stove.

My opinion, of course, but given as the idea of the forum is to help folks with the best possible courses of action, it is important to understand that this is not a competition for who can get the lowest published numbers...

Anything which meets the standards is extremely clean and efficient....and one stove tested at 4 GPH may work better in your or my home than one tested at 1 GPH.

Summary: Until you see a independent, reputable published study comparing stoves IN THE FIELD which shows that this performance tracks the EPA numbers, it would be prudent to stop suggesting the folks shop in this fashion.

My opinion, for what it's worth!

As far as another thread here about pioneering, I surely don't want to spend 2 grand on the newest model only to find out that it doesn't work right in my situation or with my wood due to the highly tuned nature of the unit.

The innovation will continue to happen whether or not we buy a 3GPH or a .7 GPH stove, but more than anything we want a stove that works in many various situations as opposed to perfect wood, chimney, operator, weather, etc.

Web...you miss the point.....true, there may be other "yardsticks" with which to measure stove performance but you have failed to produce any other reputable yardstick with which to measure performance...given the absence of any other measuring system, the best one IS the EPA approved gph figure. If you disagree, please produce another valid measured datapoint that would allow a person to purchase a better stove..... thought so...there isn't one......Elk...you stand vindicated.....

 

[Corie]

The best figure is grams of emissions per kilogram of wood. EPA adopted that for the new testing program related to only open fireplaces. Its a shame they didn't adopt it for the original wood stove program as well.

 

[Gunner]

I'm willing to bet most people outside of hearthnet have no idea what the EPA gph for their stoves is, and don't really care.

It sounds like we are using gph as some measure of efficency, it is my understanding that the two are not directly related.

 

[elkimmeg]

Gunner if one wants to argue a case with anti smoke people, one has to use some given statistic. The Epa requires the GPH one, This is in no way, a thread to
compare one manufacturer against another using GPH. Just an index to prove manufactures are going in the right direction of producing clean burning stoves, than the EPA mandate.
Your stove twice as clean as the minium EPA requirements. This is also not meant to be a competition of stoves, but fighting with anti smoke people, it is best to single out the stoves with the least GPH.. I never said the GPH is the most important criteria for stove purchases. IT is one fractor

 

[webbie]

You are correct, Gun.

gph does not relate in any exact manner to efficiency nor to ease of operation.

It would be easy to burn wood very hot and get the GPH down, and yet throw a lot of heat up the chimney which would cause a low heat transfer efficiency.
You are also correct that virtually NO ONE outside of this forum uses these figures. I remember it being used years ago for a short time (Avalon claimed the cleanest EPA back in the early 90's), but after that it was dropped from most all literature...and if it is shown, it is often in small letters. This was done for a number of reasons, not the least of which is due to the fact that many stove tags do not display the actual test results, but rather a range of similar stoves....and they often state "not tested for efficiency".

Nothing wrong with crowing about these tests, but I would never use these results myself for stove shopping or comparison.....and it is really silly to compare any which are close - like within 100% of each other. (2 GPH as opposed to 1.0, etc.).....

As to the VC test specs, what will happen once the stoves are used for a couple weeks and some ash builds up in the bottom or in other places? I ask not for an answer, but just to comment that a true test would fire the stove in the field with cordwood after a couple weeks or months of use.

For many years, the EPA has told us NOT to use these numbers for stove comparison. Even today, both the state and EPA sites and articles about stove shopping and selection do not mention comparing stoves by GPH. Instead, they use the more common methods such as we discuss here often - dealer advice, size, cat, non-cat, etc.

So, again, nothing wrong with quoting numbers, but it does no match the real story.

 

[begreen]

Elk, check the links I posted earlier. They are done by the EPA (and Canadian equiv.) with an automated wood stove emission sampler (AWES) which is an emissions test over time. The EPA tests were done over 3 weeks for most tests.

 

[Gunner]

Gunner if one wants to argue a case with anti smoke people, one has to use some given statistic. The Epa requires the GPH one, This is in no way, a thread to
compare one manufacturer against another using GPH. Just an index to prove manufactures are going in the right direction of producing clean burning stoves, than the EPA mandate.
Your stove twice as clean as the minium EPA requirements. This is also not meant to be a competition of stoves, but fighting with anti smoke people, it is best to single out the stoves with the least GPH.. I never said the GPH is the most important criteria for stove purchases. IT is one fractor

The anti- smoke people think the EPA is a joke, this has been said on the BI site before. They are quick to point out the rise is particulate after testing (even tho the #'s they claim are false)

Not wanting to get into the cat debate, but they (cats) are going to have a larger increase in gph AFTER testing than a non cat. They(cats) may not be the best recomendation when after all that is the basis for there whole argument against new EPA cert stoves, the sharp rise in particulate after testing.

IMO proper burning practices with any EPA cert stove is what should be stressed to the anti's.
It looks nice on paper to recommend a .7gph stove to them, but that is not why they are complaining about a smokey neighbour! One epa cert stove to the next is not going to make a bit of difference to the amount of smoke in their neighbourhood. It's all about the operator.

 

[begreen]

Agreed Gunner, I don't think there's a snowball's chance in hell that any argument will convince BI leaders to burn wood. However, the posts do hopefully get the BI readers to consider an alternate POV. If we can get them into a dialog with their neighbors instead of banning them, then I think it's mission accomplished.