Apples and Oranges????

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Harley

Minister of Fire
Apr 11, 2006
997
Ashfield, MA
Just doing a little research, probably will replace the stove this year. I’m getting a little confused as to what is the right “size” stove, BTU-wise. What is the consensus? Do you go by the max BTU output, or by the manufacturer’s “heating area” estimate? All the info below came from the various manufactures web sites, except for the last column, which is simply a calculation I did (and actually not sure if it is meaningful).


Manufacturer-------------------Model----------------------Max BTU------------SF--------------BTU/SF


Woodstock Soapstone-----------Fireview-------------------55,000-------------1,600-----------34.38
Jotul-------------------------------F500 Oslo-----------------70,000--------------2,000----------35.00
Jotul-------------------------------F 600 Firelight------------81,500--------------2,500-----------32.60
Lopi--------------------------------Patriot--------------------66,800--------------1,000-----------66.80
Lopi--------------------------------Liberty--------------------74,300--------------2,500-----------29.72
Osburn----------------------------1600-----------------------70,000--------------1,800-----------38.89
Buck-------------------------------80-------------------------40,500--------------2,600-----------15.58
Harman---------------------------Oakwood------------------42,000--------------2,000-----------21.00
Vermont Castings----------------Defiant Cat----------------55,000--------------2,400----------22.92
Vermont Castings----------------Encore Cat----------------47,000--------------1,900-----------24.74
Vermont Castings----------------Defiant NC----------------60,000--------------2,400-----------25.00
Vermont Castings----------------Encore NC-----------------40,000-------------1,900------------21.05


Hopefully you can see where I’m confused. How can the Harman, at 42,000 BTU be OK for a 2,000 sf home, while the Jotul has to make 70,000 BTU’s to get the job done?

Is there some difference for efficiency? In the example above, does that mean the Jotul “wastes” 28,000 BTU in comparison to the Harman? I doubt that, but not really sure how to interpret the above little sample.

Am I missing something here? The only other mention of BTU’s were on the VC website which listed a much lower BTU output for each of the stoves, and referred to it as “range test” method.

I hope this isn’t re-hashing something that’s been discussed before, but I didn’t see it in going through old posts.
 
reduce manufactures claims by 1/3 and that is probably about right
2000 sqft home means little, if rooms are closed off. All wood stoves are area heaters.
It takes an open floor plan to distribute heat in a more even fashion. Start tell us a bit about the home.
The chimney location and the room in which the stove will be installed. From here members can advise
what they think will work.
 
Thanks, Elk.... you are quick today... I just tried to fix the chart and make it a little more readable (I guess I should have previewd it before posting).

I guess my question is more general in nature right now. To me, from what I read on the manufactures websites, I could walk into a Harman dealer, tell them I have a 2,000sf house, and they might say that the 42,000 BTU Oakwood would do the trick.

If I then go down the street to the Jotul dealer with the same 2,000sf house, they might say the 70,000 BTU Oslo is what I should have. (I understand your comment about layout, etc.... but for right now - I'm just wondering about the manufacturer spec. comparisons)

My question would be.... How can that be??? It seems BTU output doesn't equate easily into square footage when you look at different manufacturers.
 
Harley said:
Thanks, Elk.... you are quick today... I just tried to fix the chart and make it a little more readable (I guess I should have previewd it before posting).

I guess my question is more general in nature right now. To me, from what I read on the manufactures websites, I could walk into a Harman dealer, tell them I have a 2,000sf house, and they might say that the 42,000 BTU Oakwood would do the trick.

If I then go down the street to the Jotul dealer with the same 2,000sf house, they might say the 70,000 BTU Oslo is what I should have. (I understand your comment about layout, etc.... but for right now - I'm just wondering about the manufacturer spec. comparisons)

My question would be.... How can that be??? It seems BTU output doesn't equate easily into square footage when you look at different manufacturers.

There is a good discussion of BTU figures related to some stove here:

http://www.chimneysweeponline.com/hobtucmp.htm

Not the two you are looking at but an eye opener just the same.
 
I noticed that too, but a lot of times it's the difference in using test wood vs cord wood.
 
Good Info there BrotherBart. I'm glad it wasn't me not seeing the something there. It does seem confusing. Does it then make more sense to compare sf heating estimates, rather than BTU output?. And obviously having to consider Elk's comment regarding layout. It seems the manufactures publish max btu. The only one in my sample that listed the EPA method was VC.

More research to do... but leaning heavily torward the Defiant or Encore
 
Look more at firebox size than BTU ratings. You'll also want to pay attention to efficiency as well. Ask around a stove may heat 2000 sq. ft. in one place but due to climate may only heat 1000-1200 in another place.
 
Well, in knowing the BTU rating for the stove is a GREAT place to start. We wont sell a stove to a person based on the square footage of the home solely. There are FAR too many variables to generalize like that. Knowing the BTU rating for each stove though is a good way to compare brands tho. Elk made a good point...How open is the floor plan? How much glass is in the house? How much insulation? What are the regional lows for the winter (easier to heat a house in Maryland than in Vermont). What does the particular homeowner view as comfortable? (I like 65 degrees, but my parents are comfortable at 80 degrees).
That being said we've a huge contingent of customers who just come in saying theyve got 2000 square feet they want to heat...what stove will do it? Usually prompts a half-hour discussion.
 
Harley said:
Good Info there BrotherBart. I'm glad it wasn't me not seeing the something there. It does seem confusing. Does it then make more sense to compare sf heating estimates, rather than BTU output?. And obviously having to consider Elk's comment regarding layout. It seems the manufactures publish max btu. The only one in my sample that listed the EPA method was VC.

More research to do... but leaning heavily torward the Defiant or Encore

Now ya just have to hope that EPA wasn't hotter than VC could ever get it up to full open. ;-P
 
I agree with Shane, Go by firebox size. For a 2000 sq ft house I would go with a 2 cu ft or more sized firebox. But beware, those firebox sizes could include the area above the baffle. For example, my Fireview has a just over 2cu ft firebox and my old Hearthstone homestead stated the same size. Well the Fireview is much larger than the Homestead. They had to include the area above the slanted baffle as part of the firebox. I get way more wood inside the Fireview.

Those high BTU numbers are probably fudged to make their stoves sound more impressive. In the real world you won't need to run a stove wide open all the time and maintain 70,000 to 90,000 btu's to heat your home.
 
The BTU rating from the stove (minus exageration) is the input side of the equation. That is the amount of heat being put into the house, regardless of square footage. What the stove shop doesn't know is how fast and much heat is leaking out of the house and how well the heat will be distributed. That's the output side of the equation. Without knowing that, matching stove size to sq. ftg. is just an estimate.

In other words, house #1 might be a modern, 6" walls, tight windows, well insulated 3000 sq ft home and house #2 might be a leaky 1500 sq ft farmhouse. It may take the Defiant to heat the smaller house, while the Encore might easilly heat the bigger box. (not considering burn times, just btu output).
 
A lot of info to look at, and I appreciate all of the input. As far as the house layout, etc. some of that is in the "swapping out a stove" thread from earlier on. so I don't want to be repeating it here. From that - I think I will be doing the lining of the chimney first, then looking for a replacement for the existing stove. I guess the original question as far as the comparison to "maximum rated BTU's" was answered pretty well, and unless I interpreted anything wrong, the concensus seems to be they are not really a good benchmark to go by. (to be honest - that's kind of what I thought all along) But I wanted to try to be sure I wasn't missing anything.
 
For what is is worth I run two VC stoves. Very soon both will be cat stoves. Part of my decision is supporting
American manufacturing jobs still in USA. The only existing foundry is VC in Bethel VT. Most others out source to
China. Are they the best, that debate could consume all discussions. The Defiant is the cleanest burning wood stove
ever tested by the EPA. If you have a good draft then consider a cat stove. Jotul has always made a quality stove as
does Harman. and many others. I am going to swap out my Resolute Acclaim for an Encore.
Describe your room and current purposed setup? How does it open to the rest of your home?
 
elkimmeg said:
For what is is worth I run two VC stoves. Very soon both will be cat stoves. Part of my decision is supporting
American manufacturing jobs still in USA. The only existing foundry is VC in Bethel VT. Most others out source to
China. Are they the best, that debate could consume all discussions. The Defiant is the cleanest burning wood stove
ever tested by the EPA. If you have a good draft then consider a cat stove. Jotul has always made a quality stove as
does Harman. and many others. I am going to swap out my Resolute Acclaim for an Encore.
Describe your room and current purposed setup? How does it open to the rest of your home?

Harmon's aren't made in PA?

Here's a little experience I have. My Osburn (made in Canada) is listed at a 1.8 cuft firebox. Look at that stove and any other with a similar size firebox (Napoleon, Lopi or Quadrafire come to mind) or even some of the VC stoves, and you'll quickly figure out that something is very wrong. Osburn claims an 18" max log size, yet I've put 22" logs in without touching the glass. The Osburn looks to be a LOT bigger. That said, my house is about 2200 sqft, and has an o.k layout for a woodstove, but far from ideal. My stove heated the house pretty well last winter...My wife wishes it were bigger...I think I agree.

If I could have handled it I would have purchased the 2200 or 2400.
 
V Heats 1800+ square foot without even trying
 
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