Need HELP I am so confused!!

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c40927

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Dec 4, 2005
3
I am a new to the forum and I have used both of the BTU calculators on this site and neither one really give me that warm fuzzy fealing that the answer I got was accurate.

I live in northwestern Oregon and recently purchased a new 2300 sq ft home. I have decided to purchase a pellet stove insert to be the primary heat source for the home. I placed on order a Breckwell P23I (mabey jumped the gun). The question I have now after really analyzing BTU input and output is..........Is this stove going to be adequate? The problem I have is unlike most manufactures Breckwell does not publish the square foot range their products will heat. Rather they leave that up to you. I realize that many factors can change this number but at least a ballpark figure would sure be nice. From what I gather Breckwell publishes a BTU INPUT of 46,000 BTU and lets assume conservatively that the stove is 80% efficient. That meens this stove has about 38,000 BTU OUTPUT. Will that be enough?? I compared those numbers to some of the other manufactures published numbers, here is what I found..........

Quadrafire says 30,000 BTU will heat 1500 sq ft
says 40,000 BTU will heat 2500 sq ft

Winslow says 37,000 BTU will heat 2000 sq ft

Harman says 42,000 BTU will heat 1400 sq ft

So as you can see there is a huge difference between the manufatures on how much heat will heat how much space. Any thoughts??
 
Yoy can figure the BTU input of any stove if you know its firebox size. The BTU input will be directly proportional to the firebox size, provided you are using the same kind of wood and loading the firebox approx the same fraction per load.

If you look at other manufacturers stoves with the same firebox size and see what they say as far as far as heating capacity, (square footage), you will get a pretty good idea.

If you are a geek like me you could do as I did - turn off the house heating system on a cold enough day during a period of time the outside temprature isn't expected to change much. Keep it off for a couple of hours or so, and figure out how fast the house temp dropped during a time the outside temp was roughly constant. Once you know the rate of temp drop, you can compute the rate of heat loss because you know the volume of your house and the density and heat capacity of air. This does assume that most heat loss is from the air in the house, but it does give you an idea. Once you know that you can figure what rate you need in BTU/hr to keep the temp at a given point.

This is only an appproximation, so once you get your figure compare it with the various heat loss calculators (there is one on this site) and see that you have something which makes sense.
 
That is the wonder of marketing literature. How can the manufacturer accurately determine the cu. ft that the stove will heat without knowing the house? There are too many variables. The difference from one home to the next can be huge depending on what temperature the house is kept at, insulation, tightness, average outside ambient, ceiling heights, etc.. Your new house should be very well insulated and it's in a very mild climate zone. I suspect you'll be fine.
 
Thanks everyone for the helpful insight. Unfortunately because this is a brand new home and this will be out first winter, I dont have any heating records from last year. To provide you with more info, the house is fairly tight and seems to not have a ton of heat loss. Also the temps in my area are not that extreme. An extreme cold day would be 38F Hi and 27F Low but those days are very rare. Usually the days we have been seeing are 43F Hi and 34F Low. So hopefully this puts things in perspective. Do you think my calculations are correct on the BTU output on the Breckwell P23I? Do you know anyone with the P23I or any Breckwell for that matter. Thanks guys!!!
 
I'm heating my house with the Quadrafire pellet stove and am located quite a bit north of Portland. My house is a leaky 2000sq.ft. 80 yr. old farmhouse. We heat it to 68 with the pellets stove. It's 36 outside now and the Quad is heating us well. Your Portland house is new. I think you have a very good chance of being just fine. If it drops below 30 you may need to kick in supplemental, but that is not common and usually passes in days. We use the Jotul for this and for comfort to bring the house up to 70-72 when we are home in the evenings.
 
You can easily verify the maximum input BTU number if you know the size of the firebox. For a hardwood like maple, for example, it weighs 28 lb/ft^3. If you know the frebox volume, you can multiply that by this number to get the total maximum weight of one firebox load. Heat value of wood is 6500 BTU/lb, so multiply by this to get the total input BTU. Then it depends on the burn rate you use - divide this input BTU nuber by the hours for a complete burn and you have your BTU/hr.
 
Hotflame, this is a pellet stove.

Interesting to note, my brother in law is heating a 2300 sq ft house on 2 cords per year in South Salem, NY. Granted, it's very well insulated, but it can be done.
 
Oops - should have read carefully. Don't know what I can say about a pellet stove. Perhaps you can see how quickly the the stove burns through a bag of pellets and figure it out that way. But I just don't know enough about how those work to be sure.
 
For pellets, figure about 8500 BTUs/lb. We average about a bag a day. 40 x 8500 = 340,000 BTUs. I suspect a new house in Portland will do a lot better. By the way, there is a really excellent consumer guide on pellet stoves on this site at: https://www.hearth.com/what/pellet/pellet1.html
 
WOW, you guys have been so helpful!!!! Thanks so much for all of the info. I am feeling a little better about my decision now. One thing I forgot to mention is that this is a new two story home in which the pellet stove will be on the first floor. To distribute the heat eavenly throughout the house would you reccommend I use the central heat/air fan to do this?

BeGreen, I think Quadrafire says the 1200i (I almost ordered this one but it was a little spendy) has a 40,000 BTU output and will heat 2500 square feet. If you said yours heats your leaky 2000 square foot home, I am feeling more confident about my P23i (38,000 BTU) heating my one year old 2300 square foot home. Thanks again for all the info!!!
 
What impresses me the most is that this is a 1980 home. He designed and built it. It has staggered 2x4s for an 8" wall and a ton of ceiling insulation. I remember him being obsessive about caulking too. They heat mostly with a wood-fired boiler, that he says is usually just idling. He also built in a wood-fired bread oven that my sister likes to keep going when she isn't working. I've been there in the middle of winter and they are cozy at around 72 degrees.
 
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