Please help me choose stove size

[joe765]

hello,
My girlfriend and I are building a house and want to use a pellet stove as the primary heat source. I've been doing a lot of research, but feel like I'm not much closer to answers.

We are building in Montana. We regularly hit 20 below zero (f). Last year the mercury read -35 for about a week. Winds up to 60 mph. It gets chilly.

Our house is small, 24x24, (576 sq ft) but we have a cathedral ceiling and a loft (about 250 square feet). The south (short) wall is 10', the north is 18'. Walls will have r-19, the lid r-30, both fiberglass batts.

My question is how many BTUs should I be looking for? I want to make sure we're plenty warm, but I don't want to overkill it and end up getting a bunch of creosote buildup.

 

[kappel15]

Most stoves tell you how many sq. feet they will heat. Just need to pick a brand that has a dealer in your area, who is also reputable and will be there after the sale if there are any issues. kap

 

[joe765]

Most stoves tell you how many sq. feet they will heat. Just need to pick a brand that has a dealer in your area, who is also reputable and will be there after the sale if there are any issues. kap

I've seen that, but they say "heats up to blah square feet." I'm assuming that I can't take that number and assume it applies to me. The same size house with the same insulation in different climates will require different sized furnaces. I just don't want to end up buying the wrong stove.

 

[nailed_nailer]

For a stove in house that size I'd be looking at 60K BTU+.
You can always turn down a stove.
For primary heating you might be better looking at Pellet furnaces.

You also have to plan for pellet storage. You are gonna burn 3-5 tons of pellets at those temps. Better to have them on hand for the year then go searching for pellets in mid-February only to be told there is a shortage.

Not sure about your area but here the insurance companies won't accept a pellet stove as a primary heat source.
---Nailer---

 

[Zeus]

I've seen that, but they say "heats up to blah square feet." I'm assuming that I can't take that number and assume it applies to me. The same size house with the same insulation in different climates will require different sized furnaces. I just don't want to end up buying the wrong stove.

Hi joe, my opinion would be to have a reputable tech come out from your area to recommend a stove. If you get a thermostat controlled stove going with a larger stove won't be a problem, with your cold temps there I would lean towards 60,000 btu as nailer suggested. Good luck let us know what you find.

 

[bogieb]

With the cathedral ceiling your main issue will be keeping the heat down on the main floor while keeping the loft at a reasonable temperature (as in, not 90*). I don't know how well ceiling fans will help force the heat lower - hopefully someone with that sort of configuration will chime in.

Also, with high ceilings, you can't go strictly by square feet. I would be inclined to believe that you are actually heating twice your main floor size - so 1,100 sq/ft (or more).

Sorry, don't have3 any answers for you, just some things to consider.

PS - I would also be inclined to go with a larger stove than you finally think you will need. Much easier to run the stove at a low setting than get more out of it than it is designed for. You shouldn't have to worry about creosote as you would for a wood stove.

 

[bags]

Bogie hit two valid points that I caught also. 1) Pellet stoves run creosote free unlike wood stoves for the most part. If you see creosote in pellet venting there are serious issues but don't worry because you will likely never see any running a pellet stove. 2) With the winter temps you can experience go with a stove that is rated for a larger space than what you have.

I would guess you could cover what you are trying to do with a 40K + BTU stove. As mentioned above I'd definitely go a little bigger as you can set many or most stoves for current heating needs by adjusting down but you can't get ore out of a stove that is rated for say 30K BTUs as it may max out and not be able to keep up with the extreme cold.

For instance I heat mainly with a P68 Harman. When it isn't real cold outside (shoulder seasons) I just turn the stove stat or settings to where I want the inside temp and it keeps it there. Many stoves will run much like a central HVAC system where you set a temp and they kick on and off as needed.

I would be looking at a stove like the P43 or P61 Harmans or something comparable. There are many options. Are there any local pellet stove dealers around you? I know Montana can be quite remote in some areas. Where are you?

 

[kappel15]

And I would make sure to have a back-up heating system, for if the stove goes down for a repair.

 

[rona]

Harman P68, Quad AE, Bixby Each would be big enough Most stoves will say 40,000 btu . I suggested bigger - 50,000, 60,000, 68,000. Its much better to get one a little bigger then to have bought one one size to small. Most stove run most efficient at 75% of their rated btu. When they go into the last 25% you will see more wasted heat out the exh system. Truthfully when they rate stoves they go by how much pellets they can burn in a specified amount of time rather then how efficient they are in capturing the heat and disbursing it in the room rather then out the exhaust.
I am sure I missed some good stoves but only listed what I have experienced.

 

[bostonfan49]

.....as nailed_nailer said, not only pellet storage, but storage inside near the stove. Opening a door to the outside in those temperatures is just wacko crazy!
Also for safety/liability reasons (since your spending major bucks on your new home) Get your chimney/exhaust professionally cleaned once a year and make sure your insurance company gets a yearly copy to prove your maintaining a clean stove......assuming the stove is acceptable to your homeowners policy.
Good Luck, Bill