Waulie said:
Calm down man, no one has called BS on Woodstock and if I was them I would throw this chart up for marketing to, however many of us on here know that the chart in this thread is pretty far up the ridiculous scale and doesn't hold water.
Anyone post this yet? EPA stove comparisons from Woodstock...
- Thread starter Woody Stover
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
- Status
Calm down man, no one has called BS on Woodstock and if I was them I would throw this chart up for marketing to, however many of us on here know that the chart in this thread is pretty far up the ridiculous scale and doesn't hold water.
impressive, but its not that uncommon for a small firebox to show a higher output in the epa test,
however also you have to look at the difference in firebox size in another way. a pound of wood contains on average about 8500 BTU of potential, in a 1.5 CF firebox you arent gonna get as much wood by weightt into the box, so the load will last a shorter time, so you figure just to make math easier a 10 lb load at 8500 BTU potential, you have 85000 BTU now, if that load takes 2 hours to burn you get 42,500 (again, im just making the math easier)
now, take the 3.5 CF firebox load 23 LBS of the same 8500BTU wood (2.3 times capacity on ratio) you get 195,500 BTU, assume now that you take 4.6 hours to burn it, you still average 42,500 per hour so for the same overall output you would have to reload the smaller stove 2.3 times to achieve the same result
that said, the keystone is a great little stove, but if you look at the epa test ratings, http://www.epa.gov/Compliance/resources/publications/monitoring/caa/woodstoves/certifiedwood.pdf
our "13-ncmh" a 1.8 CF firebox unit outheats the 30-nc as well as looked at in the chart above. it makes for a great selling point and as i said, the keystone is a great little stove, but its a little stove, it dont want none of a head to head load for load battle with the 30, its not a fair fight cause its a small stove and the 30 is a big one, not apples to apples
however also you have to look at the difference in firebox size in another way. a pound of wood contains on average about 8500 BTU of potential, in a 1.5 CF firebox you arent gonna get as much wood by weightt into the box, so the load will last a shorter time, so you figure just to make math easier a 10 lb load at 8500 BTU potential, you have 85000 BTU now, if that load takes 2 hours to burn you get 42,500 (again, im just making the math easier)
now, take the 3.5 CF firebox load 23 LBS of the same 8500BTU wood (2.3 times capacity on ratio) you get 195,500 BTU, assume now that you take 4.6 hours to burn it, you still average 42,500 per hour so for the same overall output you would have to reload the smaller stove 2.3 times to achieve the same result
that said, the keystone is a great little stove, but if you look at the epa test ratings, http://www.epa.gov/Compliance/resources/publications/monitoring/caa/woodstoves/certifiedwood.pdf
our "13-ncmh" a 1.8 CF firebox unit outheats the 30-nc as well as looked at in the chart above. it makes for a great selling point and as i said, the keystone is a great little stove, but its a little stove, it dont want none of a head to head load for load battle with the 30, its not a fair fight cause its a small stove and the 30 is a big one, not apples to apples
stoveguy2esw said:
Great post. All the chart shows is the heat rate at the stove's highest possible burn with EPA test fuel. It doesn't mean it "throws the most heat" in the real world. It does mean, it generates the highest burning rate with EPA test fuel. It is not meaningless and certainly not BS, but it also doesn't tell very much of the story. It would be fantastic if someone would do objective heat ouput and efficiency testing with all wood stoves under real world burning conditions. Until that happens, we're left with marketing fluff and reviews on Hearth.com. We all know which is better!
Waulie said:
yeah, it would be nice and thanks, i actually sat and thought about how to explain that without looking like i was being biased (which i am but i try to give credit where its due)
as for the "output into the room" real world test, would be pretty kool but it would be a mathmatical nightmare to accomplish accurately. factors like cubic inches of exposed metal to the firebox, external temps (which are different all over the average stove). we try , and i mean "try" to get a feel for rated sq footage based on the measurements we get off the particular model of stove based on achieved skin temps, fire duration etc. our estimations are subject to varience in structures obvioulsy and are by no means "dead on "accurate in every way" but they are meant to be a "guideline" rather than an actual 'specification" as im sure my fellow manufacturers are intending as well. as a practice i would say looking at stoves when shopping always bear in mind that the factors such as sq footage of coverage, burn times and the like are generally "best case" not "the norm" so firebox capacity is the "big" stat, and the others should be looked at as "approximations which give a general sense of expectations"
Yeah, it would be tough, but I think it would could be done. You just have to have a controlled environment and draft, all the stoves lined up and ready to go, and a whole bunch of time on your hands. Of course, who would pay for it? That's the big problem.
Waulie said:
I would argue that it is meaningless and does more harm than good.
Case in point is the Heritage/Equinox/Firelight/30NC comparison.
The average wood stove buyer takes a lot of these numbers at face value, and you can't fault them for doing that since the numbers seem to have science behind them. What happens is that a new buyer will look at the numbers and say "hell I should buy a Heritage to heat my 2500 sq ft home, it says here it heats a lot better than the 30NC, produces just as much heat as the Firelight, and just a little less than the Equinox."
Then comes winter and the stove isn't cutting it. This causes a lot of unhappy and disgruntled buyers and potential customer service issues.
Fact is, there is no real replacement for firebox size. You need a lot of heat? You need a large firebox. A smaller firebox stove might give you longer, or equaled, burn times, but it isn't going to out heat a larger firebox.
BrowningBAR said:
I completely agree, but that's what's frustrating. If all you have is firebox size to go off of, you might not end up as dissappointed but only because you don't know better. You don't know you could be burning less wood to stay just as warm. After all, efficiency does matter.
I also agree that someone might see that chart and think the Heritage heats better than the 30NC. Hopefully though, they're also asking questions and reading reviews. I mean I'd hate to say the EPA test results shouldn't be published for fear it might confuse someone. Once again, it is the only objective test most wood stoves are subjected to.
Waulie said:
Only to a certain extent. Here's an example:
If I had to choose between a Pre-Epa Vigilant (rated at 50,000 max BTUs) and a Heritage (listed at 55,000 max BTUs) for a 1800-2000 sq ft home I would choose the Vigilant even though the Vigilant is FAR less efficient.
It will throw more heat and have the same burn times as the Heritage. I will burn through twice as much wood, but I will be warmer. And in the end, warmth is what we are all trying to achieve.
Obviously this is an extreme example, but it does speak specifically to the point that efficiency is only worth so much when it comes to your stove purchase. I am also refraining from using Woodstock stoves so it does not seem like I am bashing them. Nearly all stove manufacturers are guilty of fudging, or manipulating, numbers to show that their stoves are superior.
My interpretation of this chart is that for x amount of wood, y btus are generated. All the stoves are loaded with the same amount of wood (x), and the btus they generate (y) is recorded. It is not for a full load of wood, y btus are generated. That is why a smaller stove can generate more btus than a larger stove, because they all start out with the same amount of wood, not a full load. Sure a larger stove will generate more btus if it has twice the load of wood, but this shows how they perform on an equal amount of wood. So, it looks to me like the Progress will give you the most efficient use of your wood by giving you the most btus/lb, but it may not give the most btus of any stove because others may be able to compensate for their relative lack of efficiency with a larger load size.
Test load size is based on firebox volume for the test. Here for everybody's reading enjoyment is EPA method 28. The specs for doing the test.
http://www.epa.gov/ttn/emc/promgate/m-28.pdf
Be sure to enjoy reading where up to 2 inches above the baffle and in some cases the ash lip can be used to determine firebox size.
http://www.epa.gov/ttn/emc/promgate/m-28.pdf
Be sure to enjoy reading where up to 2 inches above the baffle and in some cases the ash lip can be used to determine firebox size.
I do not think that efficiency is very important among epa certified stoves of similar technologies. Whether a stove emits 1 or 4 gph also has very very little bearing on the realities of wood burning. You want to talk about real world conditions then you can ignore these meaningless specs.
HollowHill said:
The issue with that is that a steel stove like the 30 should be close to the same BTUs as the Drolet.
BrotherBart said:
Well, there goes my grasp of the situation - up in smoke
Or maybe that's my brain I'm smelling burning :lol: So, if they are taking firebox size into account, it would seem to indicate that certain stoves are putting out more heat than their larger counterparts. And, 'twould seem efficiency would be the likely explanation for such a phenomenon (less wood, but more btu output). I guess my question now would be, why do some people think that this would not hold up in the real world?
HollowHill said:BrotherBart said:
Well, there goes my grasp of the situation - up in smoke
So, if they are taking firebox size into account, it would seem to indicate that certain stoves are putting out more heat than their larger counterparts. And, 'twould seem efficiency would be the likely explanation for such a phenomenon (less wood, but more btu output). I guess my question now would be, why do some people think that this would not hold up in the real world?
Really?
All it indicates is that on a "high burn" with the draft full open, the Progress has a way higher burning rate (btus/hr) than any other stove ever tested. The high burn rate by itself does not indicate that the Progress puts out more total heat than any other stove, small or large.
The high burn rate by itself really doesn't mean a whole lot. Although, the fact that it had the widest range of burn rates ever tested does indicate that overall the stove has a wide range of burning rates even in the real world. The tests do show that with the same load of wood, the Progress can produce an incredibly high burn rate or a very low burn rate. That, coupled with the very low emissions, does mean something to me. No, it doesn't mean the Progress heats twice as well as the NC30 or anything like that. But, the fact is that for all it's faults in comparison to the "real world", the EPA tests remain the only objective test that wood stoves are subject to.
I've acknowledged several times the limitations of the test and recognize that the chart is a marketing document that could be misleading. I disagree that the only objective tests that we have to compare wood stoves are completely meaningless. If they are, then the only data that should ever be given any weight is firebox size. And, not the firebox size that the manufacturers report because those are also meaningless. Personally, I believe there are different technologies,configurations,draft controls, quality, that do make a difference in real world heating applications. Once again, I find the results interesting because not other data has even the smallest meaning since it is not based on consistent test methods.
The high burn rate by itself really doesn't mean a whole lot. Although, the fact that it had the widest range of burn rates ever tested does indicate that overall the stove has a wide range of burning rates even in the real world. The tests do show that with the same load of wood, the Progress can produce an incredibly high burn rate or a very low burn rate. That, coupled with the very low emissions, does mean something to me. No, it doesn't mean the Progress heats twice as well as the NC30 or anything like that. But, the fact is that for all it's faults in comparison to the "real world", the EPA tests remain the only objective test that wood stoves are subject to.
I've acknowledged several times the limitations of the test and recognize that the chart is a marketing document that could be misleading. I disagree that the only objective tests that we have to compare wood stoves are completely meaningless. If they are, then the only data that should ever be given any weight is firebox size. And, not the firebox size that the manufacturers report because those are also meaningless. Personally, I believe there are different technologies,configurations,draft controls, quality, that do make a difference in real world heating applications. Once again, I find the results interesting because not other data has even the smallest meaning since it is not based on consistent test methods.
ohlongarm
Minister of Fire
BrowningBAR said:HollowHill said:BrotherBart said:
Well, there goes my grasp of the situation - up in smoke
So, if they are taking firebox size into account, it would seem to indicate that certain stoves are putting out more heat than their larger counterparts. And, 'twould seem efficiency would be the likely explanation for such a phenomenon (less wood, but more btu output). I guess my question now would be, why do some people think that this would not hold up in the real world?
Really?
Yup, really. To me it's not so farfetched to think that something can be smaller and still do a better job. For instance, in the world of computers, the computers of the 1940s and 50s could fill a room, but still not store as much data or work as quickly as today's much smaller netbooks. Rumford, by angling a fireplace's side walls somewhat lessened the size of the firebox, yet increased the heat output by doing so. So, yes, I do not find it that difficult to imagine that advancing technology might generate more btus in a smaller space.
HollowHill said:BrowningBAR said:HollowHill said:BrotherBart said:
Well, there goes my grasp of the situation - up in smoke
So, if they are taking firebox size into account, it would seem to indicate that certain stoves are putting out more heat than their larger counterparts. And, 'twould seem efficiency would be the likely explanation for such a phenomenon (less wood, but more btu output). I guess my question now would be, why do some people think that this would not hold up in the real world?
Really?
Yup, really. To me it's not so farfetched to think that something can be smaller and still do a better job. For instance, in the world of computers, the computers of the 1940s and 50s could fill a room, but still not store as much data or work as quickly as today's much smaller netbooks. Rumford, by angling a fireplace's side walls somewhat lessened the size of the firebox, yet increased the heat output by doing so. So, yes, I do not find it that difficult to imagine that advancing technology might generate more btus in a smaller space.
I'll disagree with that comparison.
TO BE CLEAR: No one is saying that the Woodstock stove are bad. They are great stoves. If I had the cash, I would absolutely buy a Progress. That being said, the chart is a COMPLETE MESS.
Their is no way in a Jeebus that the Heritage produces more heat than the Firelight. There is no way the Heritage produces more heat than the 30NC. Their is no way the Encore produces more heat than the 30NC. There is no way the Drolet produces over twice as much heat as the 30NC.
This has nothing to do with the heating claims of Woodstock. This has to do with the heating claims of every other stove they have on the list.
This chart does more harm than good for the stove buying public.
I love my 1980 Buck AND my new LITTLE Hampton! They both keep me warm, and I love cutting wood....so I'm good. Real world. Some own a Cadillac, some own a VW. They are both happy.
Marketing BS IMO. The bigger the box the more heat potential. You may see a slight difference in efficiencies but I would think the difference is too small to even worry about.
I've often wondered how much GPH numbers factors into overall efficiency and it doesn't seem like the difference between 1gph and 5gph is really all that much.
I've often wondered how much GPH numbers factors into overall efficiency and it doesn't seem like the difference between 1gph and 5gph is really all that much.
BKVP
Minister of Fire
I can't really comment on the new comparative document mentioned here. I would however like to provide some clarification to some statements made herein. It is NOT true that all wood heaters must be tested at approved independant test labs. In fact, we have a certified lab in our facility and under the EPA remote testing program, manufacturers can actually have their certification tests done in-house so long as the staff from the approved test labs run the actual tests.
Second, there are only a finite number of Btu's in a pound of wood. Taking into account moisture content, there is only so much heat available from a load of wood regardless of which stove the wood is burned in. Efficiency is therefore everything! Who cares how much heat a stove can produce if it cannot deliver it into the home? For lab purposes and tax credits, the LHV works fine. But in the real world HHV is where it's at.
As for larger firebox sizes producing more heat, maybe. In fact, pour a cup of water into a bucket and try to absorb as much water as possible with a 6" x 6" paper towel. Then repeat the same test but use a paper towel that is 24" x 24". You will absorb more of the water because of increaed surface area. More surface area can equate to more heat transferance in the case of larger stoves, but keep in mind shielding and other obstructions can affect transferance or at a minimum perceived transferance.
There is a limited amount of absorbtion by all materials whether they be cast, stone or steel. Once the given material has reached 100% absorbtion, then the real energy transeferance is maximized.
The guys at WS know their business as well as anyone and in fact better than most. Marketing ploys aside, consumer satisfaction with thier products would indciate their products live up to their claims. (By the way so do ours!)
Chris
Second, there are only a finite number of Btu's in a pound of wood. Taking into account moisture content, there is only so much heat available from a load of wood regardless of which stove the wood is burned in. Efficiency is therefore everything! Who cares how much heat a stove can produce if it cannot deliver it into the home? For lab purposes and tax credits, the LHV works fine. But in the real world HHV is where it's at.
As for larger firebox sizes producing more heat, maybe. In fact, pour a cup of water into a bucket and try to absorb as much water as possible with a 6" x 6" paper towel. Then repeat the same test but use a paper towel that is 24" x 24". You will absorb more of the water because of increaed surface area. More surface area can equate to more heat transferance in the case of larger stoves, but keep in mind shielding and other obstructions can affect transferance or at a minimum perceived transferance.
There is a limited amount of absorbtion by all materials whether they be cast, stone or steel. Once the given material has reached 100% absorbtion, then the real energy transeferance is maximized.
The guys at WS know their business as well as anyone and in fact better than most. Marketing ploys aside, consumer satisfaction with thier products would indciate their products live up to their claims. (By the way so do ours!)
Chris
- Status
Similar threads
