Pellet Stove Tests

[begreen]

The results are in from the Alliance for Green Heat:
http://forgreenheat.blogspot.com/2015/10/study-of-pellet-stoves-shows.html
Full report:
(broken link removed to http://www.forgreenheat.org/decathlon/intro.html)

 

[bostonfan49]

The results are in from the Alliance for Green Heat:
http://forgreenheat.blogspot.com/2015/10/study-of-pellet-stoves-shows.html
Full report:
(broken link removed to http://www.forgreenheat.org/decathlon/intro.html)

What an excellent read! I appreciate the part about cleaning, that you have one group that does all the daily, weekly and monthly plus cleaning/maintenance and the other group that more or less runs 24/7 and does minimal cleaning and maintenance. Judgement aside, a great article for any potential newbie.....Thanks, Bill

 

[begreen]

Yes, it's great to see some objective comparative testing of popular stoves.

 

[smwilliamson]

You're welcome

 

[John Ackerly]

So, yes, Scott was very instrumental in this report, but I should emphasize that the testing alone dictated the ratings. I expect many folks will take issue with results. And it may be that the Piazzetta, for example, is a fabulous stove if you use high quality pellets and clean it every day - or even just use ordinary pellets and clean it every day. Our results were based using Curran pellets (80/20 hardwood softwood mix). We hope to do some more testing later this fall with really high and really low quality pellets to see how much emissions, efficiency and maintenance are impacted on these stoves.

One question for hearth.com. Where is your fuel calculator? We have been urging everyone to use it, since we think its the best one out there, but the link doesn't work anymore and I can't find it. In the report, we directed folks to another relatively good calculator, but not near as good and the old hearth.com one.

John

 

[begreen]

One question for hearth.com. Where is your fuel calculator? We have been urging everyone to use it, since we think its the best one out there, but the link doesn't work anymore and I can't find it. In the report, we directed folks to another relatively good calculator, but not near as good and the old hearth.com one.

It's in the shop getting converted over to modern code used on the site. Hopefully it will be back soon in the Articles section.

 

[begreen]

I find it interesting to note how much lower the actual AGH measured heat output was as compared to marketing figures which could be input or output or ?? BTUs.

 

[tiger]

Full report:

I may be rationalizing, but it sounds like my Accentra was a good choice for someone like me living far enough South that I often burn at a lower setting... maybe not so much for more extreme climes?

 

[LuvMyPellets]

Not sure I am crazy testing free standing stoves vs inserts but that is just me.

 

[F4jock]

I don't understand how you can rate an insert along with a freestanding. Radiant heat alone obviates this.

When my wife and I competed in equestrian sports we had a saying, "Horses for courses." Essentially, that means that if you are going to do dressage and when you need a different type of horse then if you are going to do open jumping or eventing.

This test reminds me a lot of a consumer magazine, a very famous one, that usually lumps everything in one category together without considering the difference in usage and application. For instance, my Corvette is not a minivan but they tend to lump them together.

I think that these testers tended to do that same thing. Also, insofar as efficiency is concerned, having had wood stoves and pellet stoves, snd even though on my acreage wood is free, I'll stick with the pellets because of the lower maintenance as a past firefighter, the higher safety coefficient. To h*** with the so-called efficiency.

To paraphrase the title of a not so famous movie that I like very much, "Take this test and........."

 

[NHcpa]

Not surprised the 52i got a "1" on cleanliness. Am I missing why it only got a one (ie ease of cleaning (it's a pullout - hence difficult) or it's just a nasty stove? Anyway, I give it a one also on cleanliness regardless. I think the other score ratings I would also agree. I will just add, that when others ask me how I like pellet compared to my wood stove, my response is.... A pellet stove and wood burner, is like a car with a carburetor... both will get you there but with a pellet stove, you have to breakdown the carb to clean after 20 tankfulls of gas...

 

[reallyte]

A very nice information source for sure. I personally would have preferred the standard scientific article format but a good read. In general, kudos for the side suggestions for consumers. These buying suggestions are light years ahead of anything available on the Web right now (not to mention the things that are echoed in every thread here). Any chance there is a pdf format with everything together? The information felt a bit fragmented.

 

[Wilbur Feral]

I don't understand how you can rate an insert along with a freestanding. Radiant heat alone obviates this.

When my wife and I competed in equestrian sports we had a saying, "Horses for courses." Essentially, that means that if you are going to do dressage and when you need a different type of horse then if you are going to do open jumping or eventing.

This test reminds me a lot of a consumer magazine, a very famous one, that usually lumps everything in one category together without considering the difference in usage and application. For instance, my Corvette is not a minivan but they tend to lump them together.

I think that these testers tended to do that same thing. Also, insofar as efficiency is concerned, having had wood stoves and pellet stoves, snd even though on my acreage wood is free, I'll stick with the pellets because of the lower maintenance as a past firefighter, the higher safety coefficient. To h*** with the so-called efficiency.

To paraphrase the title of a not so famous movie that I like very much, "Take this test and........."

Oh, please... It's a very reasonable test. One can find many things to pick at with any test of this type, but it gives the consumer some guidance.

Did your stove not come out on top? Well, put on your big boy pants and go develop your own test, then. Otherwise, it's a reasonable service, and worth at least every penny you paid for it.

 

[BrotherBart]

Damn it. I got up this morning loving my 25-PDVC and now I am going to go and throw an empty beer can at it and put a pot plant on top of it.

 

[Cory S]

They should have tested a P43/P61 free standing in that test.

 

[F4jock]

Yep Will. I paid nothing and that's about what it's worth.

Before you start demeaning people maybe you should review the scientific method of evaluating mechanical devices like for like and the proper presentation of data. Now I could get snarky like you and posit that while I was taking engineering courses you were apparently enrolled in the Liberal Arts equivalent of "How to insult people who disagree with you" . . . . But I won't.

Back to facts. Just because a stove burns pellets doesn't mean it is the equivalent of every other stove that does the same, just as because a car has four wheels doesn't mean all cars are equal. An insert cannot be properly equated to a free-standing stove. Period. For example, radiant heat from an insert will be more directional and probably less. Positioning a free standing can optimize radiant distribution whereas an insert is limited in this respect. The works of an insert are also, of necessity, confined to a fixed location whereas . . . . . You get the idea I hope.

One of the main questions deciding one on a pellet stove and further the type one gets is "Can I heat my house for less than using conventional methods such as oil gas or electricity and can this be done with an acceptable amount of labor." The next consideration is placement; will an insert replace my inefficient fireplace and provide enough heat or should I go free-standing? And of course an insert is more difficult to clean and service! Duh! Thank you Captain Obvious!

As well, we could have heated with free wood from or acreage or more cheaply with coal, but wanted auto-ignition and lower maintainance compared to a woodstove stove thus chose pellets. Efficiency played almost no part in the choice except as an initial ballpark cost comparison with oil.

 

[John Ackerly]

I don't understand how you can rate an insert along with a freestanding. Radiant heat alone obviates this."

A few things to consider here: first, when EPA accredited test labs test inserts for certification, they are freestanding - not enclosed in a fireplace. To some extent, we were trying to mimic how labs tested stoves. Second, if anything, the efficiency numbers would likely be slightly higher testing inserts without putting them in a fireplace. Third, we did some infrared photos and it was pretty impressive how cool the backs of those stoves were and how effectively they direct all their heat to the front of the stove.

Bottom line - I doubt that it makes much of a difference, but this would be a good question for test labs folks. I asked some of them, and didn't hear any reason that testing them as a freestanding stove would make much difference. Some of the practices of test labs have become patterns though that don't make lots of sense, but may help make testing more fair, or just easier for the labs. It wouldn't be that hard for us to box in the stove and test it again. Wish we had resources to do that sort of thing. We do hope to do some comparative testing with corn and different types of pellets. Any other suggestions are welcome!

 

[John Ackerly]

It's in the shop getting converted over to modern code used on the site. Hopefully it will be back soon in the Articles section.

Thanks. We'll get a link to it in the pellet stove ratings report as soon as its back online.

 

[F4jock]

John, what I meant about the radiant heat is that a free-standing has more heated surfaces and can radiate 360. An insert radiates primarily unidirectionally. This should be really evident under low-fire conditions where the blower is off. No matter how you direct the heat from an insert the lack of radiant surface and the limited psitioning ability is going to gimp it somewhat compared to a free-standing of ostensibly the same BTU output.

 

[John Ackerly]

John, what I meant about the radiant heat is that a free-standing has more heated surfaces and can radiate 360. An insert radiates primarily unidirectionally. This should be really evident under low-fire conditions where the blower is off. No matter how you direct the heat from an insert the lack of radiant surface and the limited psitioning ability is going to gimp it somewhat compared to a free-standing of ostensibly the same BTU output.

Agreed, but much more so with a wood stove insert than a pellet stove insert. I assume folks don't use them without the blower. I always urge people to put a freestanding wood or pellet stove in their fireplace, if its big enough. Someone must have done some testing on efficiency of inserts vs. freestanding stoves. Problem is, lots of testing done by manufacturers, or by labs doesn't get published, so public can't see results.

 

[John Ackerly]

I find it interesting to note how much lower the actual AGH measured heat output was as compared to marketing figures which could be input or output or ?? BTUs.

Its easy for anyone to measure the feed rate of their pellet stove. Just start with a totally empty hopper, measure out 10 pounds or use a full 40 pounds, and see how long the stove burns. That will tell you how many pounds of pellets the stove consumed each hour. Keep stove on its highest heat output. We know most pellets are in the 8,000 - 8,300 BTU per pound range, so feed rate times BTUs gives you your BTU input. Then, you have to calculate efficiency, which is a bit of a guess game, but you could be generous and estimate 75% efficiency, and come out with the max BTUs of your stove. We have no idea how companies estimate such high BTU output since it seems physically impossible to deliver that many pounds of pellets to the hopper. EPA is also not really requiring labs to report actual BTU output, which is too bad, because information on a government website should be credible and not just relay manufacturer exaggerations.

 

[F4jock]

Nothing the government says is credible!
You expected this to magically change for wood stoves?

As long as manufacturers are consistent in whatever standard they use you can get a rough idea of which breadbox is bigger. It's when the standard changes and one doen't catch it that problems occur. If everyone cites BTU in you at least have a wayear to make an educated guess which one MAY have the highest output.

 

[smwilliamson]

John, what I meant about the radiant heat is that a free-standing has more heated surfaces and can radiate 360. An insert radiates primarily unidirectionally. This should be really evident under low-fire conditions where the blower is off. No matter how you direct the heat from an insert the lack of radiant surface and the limited psitioning ability is going to gimp it somewhat compared to a free-standing of ostensibly the same BTU output.

But that's where your wrong. A Mt Vernon freestanding stove is not going to throw any more noticeable heat than the insert of the same. Additionally I doubt you unsee stand how much work, thought and consideration we put in to this endeavor, how much money this all costs and as such, we had to kinda design the whole thing to try and give the as much useful info as we could. Ultimately John made the call to figure a rating system that localized the data and put each stove on its own merits. I mean him and I sat there in an office trying to figure out criteria for two full days and I think we could only narrow down the list to 25 things and we eventually had to pair that down again two or three fold just to make it within budget. FYI this test was NOTHING like consumer reports. We aren't favoring any one stove over another.

 

[John Ackerly]

Nothing the government says is credible!
You expected this to magically change for wood stoves?

As long as manufacturers are consistent in whatever standard they use you can get a rough idea of which breadbox is bigger. It's when the standard changes and one doen't catch it that problems occur. If everyone cites BTU in you at least have a wayear to make an educated guess which one MAY have the highest output.

Yes, but no one cites BTUs the same way. Just like efficiency. The problem is that if some companies exaggerate, it puts pressure on others to use similar ways to report BTUs or efficiency. There's not enough incentive to be accurate when your competitors aren't. Luckily, we are past all those games with grams per hour and no one tries to fudge those numbers.

 

[Zeus]

Hey guys maybe a stupid question here but what does "cleanliness"mean exactly? How dirty the inside of the stove becomes or its exhaust?