Stove sizing - too big?

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dh1989

Burning Hunk
Dec 6, 2014
130
East Bay Rhode Island
I'm trying to decide on a stove for my 1400 sqft raised ranch. Upstairs is about 1000 sqft and downstairs is about 400 sqft finished, then a garage and utility room (unheated). I was hoping to put the stove downstairs and let the heat rise up the stairwell but that may not be possible without either cutting into an already small bedroom space upstairs or drilling the concrete foundation and running an all outside chimney (draft concerns, stack effect, etc).

I currently heat with oil and have been tracking my oil use versus heating degree days this winter. Oil boiler (hot water baseboard) is about 80% efficient. Based on oil use at that efficiency, and heating degree days, I came up with these numbers:

At 55 heating degree days (about as cold as it gets here):
With heat on only upstairs (65F), 18,000 BTU/hr
If heating entire house (65F), 25,000 BTU/hr

At 20 heating degree days (shoulder season):
With heat on only upstairs (65F), 6,500 BTU/hr
If heating entire house (65F), 9,000 BTU/hr

Most of the stoves I've seen seem severely oversized if I went with the upstairs install. I was looking at Blaze King catalytic stoves, and it seems that with even the smaller stoves (such as Ashford 20/30 series) I would be running them close to low most of the time.

My numbers are based on 65F indoor temps, and my comfort zone extends up to about 70-75. If the house is in the 80s that is too hot.

Would something like the Ashford bee too big, or am I overthinking this? Thoughts?
 
I would re-do your BTU numbers based on 70 deg inside. 65 is just too cold for me. If there is an easy outside entrance to the basement from outside, I'd consider putting the stove downstairs. Do you have a ready supply of firewood for free or will you be buying it? If buying, I would consider a pellet stove upstairs. Much easier to install for chimney and more easily controlled with a thermostat.
 
Have a hard look at those BTU/hr numbers for any stove. More often than not the sales department in a company is claiming as many BTU as they can in order to say "Hey look, we have a stove big enough for you". In reality the EPA numbers use more or less a small load of construction lumber and give you the BTU number burning that load. The "maximum" numbers given are just that. They are the BTU you could get out of a stove if you stood there and stoked that thing every hour. The real world maximum is likely closer to the EPA number because you won't be constantly stoking it, but may be a bit higher because you are burning cord wood, not lumber. With your 25k BTU/hr consumption I would start my search by using an EPA rating close to that number. You can always build a smaller fire in a larger stove.
 
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Yep,always go bigger.
Like said build a smaller fire for shoulders or open a window it it gets to warm.
You want plenty of "firepower" !
 
Our house simply has a small hole cut in the ceiling/floor of each room we want the heat to go up into (with metal grate covers), and that works surprisingly well. I have a 1700 square foot cape (not particularly well insulated) in western Mass and do well with a 3.0 cubic foot stove. Of course it's pretty difficult to extrapolate to a different situation (different layout, insulation, etc.) but if I were you I wouldn't go smaller than 2.5 cubic feet.
 
What you are probably looking at are the peak BTU numbers which is the max heat that particular stove can deliver. What you want to know is the average BTUs per hour. E. g. 25,000 BTU per hour are 600,000 BTU per day or 18 mBTU per month. That's a full cord of solid hardwood like oak burned during one month. Thus, the BlazeKing 30 series would not be too big. You can throttle them down when you don't want that much heat and crank them up when it is really cold. For a more standard secondary burn stove I would look into the 2 to 2.5 cu ft firebox range; maybe more at the upper end. Just a few stoves that size: Enviro 1700 series, Osburn 2000 or Matrix, Regency F2300, Quadrafire Explorer 2, or the Englander Madison as a budget choice. There are more options. Knowing your budget, preferred style, the install location, possible flue length etc. will help in recommending additional models.

How dry is your wood supply?
 
Our house simply has a small hole cut in the ceiling/floor of each room we want the heat to go up into (with metal grate covers), and that works surprisingly well.

Not sure if I would recommend that so easily. Did you check with local fire codes whether that is permissible? Are there any fusable-link dampers in there?
 
I have a raised ranch roughly 1200 sf upstairs and 400 rec room downstairs. I have an insert upstairs which is rated for 2200 sf. It heats the house nice, however I am thinking about putting Ashford 30 in the rec room and keeping the insert. The way I think is run the Ashford all the time so the rec room stays nice and warm, and if it's really cold have the insert running too. I am sure that Ashford 30 will not cook you out of the house. I wouldn't even bother cutting any holes in the floor, the open staircase should be enough for the hot air to raise to the the upstairs. My house was built in 1994 and 2x6 construction so it's faily well insulated. If I will go ahead with the Ashford I will run triple wall SS chimney system on the outside I think it's the most cost effective way of doing it.
 
Thanks. I'm at $5000 budget total for install including stove and chimney. Give or take a bit.

Basement is ideal install but it must be an exterior chimney out the back foundation if I go that route. This house doesn't have room on the first floor to run a chimney and chase without sticking the stove in some odd spot in the middle of downstairs. Unless there is some way to install an offset thimble that runs between interior walls it won't work without major structural changes to the house.

Flue length will depend on the floor it goes on. I think I'm at about 15-20 ft if I go downstairs. I have another thread on here with my floor plan etc.

Wood supply is being built up at the moment, have cordwood (green, purchased) and unlimited access to pine mill scraps.
 
Not sure if I would recommend that so easily. Did you check with local fire codes whether that is permissible? Are there any fusable-link dampers in there?

For sure. In case of a fire, from any source, you do not want one or more chimneys built into the floors of your house.
 
Thanks. I'm at $5000 budget total for install including stove and chimney. Give or take a bit.

That's pretty good. Should make most stoves possible including a BK.
Basement is ideal install but it must be an exterior chimney out the back foundation if I go that route. This house doesn't have room on the first floor to run a chimney and chase without sticking the stove in some odd spot in the middle of downstairs. Unless there is some way to install an offset thimble that runs between interior walls it won't work without major structural changes to the house.

Any pics inside + outside of a possible downstairs location?
Flue length will depend on the floor it goes on. I think I'm at about 15-20 ft if I go downstairs. I have another thread on here with my floor plan etc.

Be aware that most stoves need a minimum of 15 ft of flue. You may run into problems when you install the stove upstairs.
Wood supply is being built up at the moment, have cordwood (green, purchased) and unlimited access to pine mill scraps.

Unless it's ash or soft maple I would not count on the cordwood being dry next winter. Smallish splits, loosely stacked, single rows, raised from the ground and top covered with as much sun and wind exposure will help. The pine may be your better option. Make sure to keep it protected from the rain.
 
Grisu:

Wood seems to be a lot of elm with some maple and ash. Still ordering more so not sure what I will have. Aiming for 8 cords stacked this summer and planning on using mostly the pine next winter.

My other thread has my downstairs pictures/floor plans. I have a walkout basement in the front so not sure if I need to worry about backdraft/stack effect with that install:
https://www.hearth.com/talk/threads/help-me-design-my-stove-install.136658/
 
A Blaze King will give you great flexibility in heating and long burn times. With the catalyst and excellent air control you can achieve low heat output when needed. It is my experience that running them like this, even with good wood (but perhaps not dried quite optimally) will result in more creosote buildup over the year than a non-cat type.

I own both types of stoves and burn identical wood in them and the EPA burn tube stove simply doesn't leave any creosote for me. I sweep it yearly but get nothing out of it versus a pail-full for the Blaze King. I will now be sweeping twice a year rather than once just to be safe as I am primarily running the Blaze King. This is a bit of a pain but totally worth it in my mind as I enjoy the ease of use (far better than a tube stove IMHO) the rest of the year. If you don't need much heat you will probably be running 24 hour loads. This is awfully nice! So if you go blaze king I would plan to set up your chimney to allow for easy sweeping. Get a cap that is easy to take on and off and a way to get up to the top easily.
 
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For sure. In case of a fire, from any source, you do not want one or more chimneys built into the floors of your house.
Sorry for giving poor advice, I didn't think about this. These were present in the house when we bought it. Maybe I need to rethink it.
 
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