Square FootAge vs BTU Question
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I'm in the Albany area of upstate New York, but I'm not sure where you are in relation to that.
A (rough) rule of thumb that we used in estimating the size of a unit for heating is the 30-40-50 rule.
Take the number of square feet you want to heat & if you have a duck's butt tight,
well insulated house, you will need about 30 BTU/Sf to heat it.
Moderately tight average insulation - 40BTU/Sf
Old windy farmhouse 50BTU/Sf (Minimum)
All of those numbers are OUTPUT. You will have to take the INPUT rating
of your appliance & multiply THAT times the efficiency to get the OUTPUT.
So, 2600 x 30 =78K BTU OUTPUT
2600 x 40 = 104K
2600 x 50 = 130K
So if your appliance is 75% efficient you'll need 104K BTU input to get 78K OUTPUT.
Bottom line? Gonna be tough to heat the entire place with one pellet burner.
You may have to close some rooms off or install more than one unit...
A (rough) rule of thumb that we used in estimating the size of a unit for heating is the 30-40-50 rule.
Take the number of square feet you want to heat & if you have a duck's butt tight,
well insulated house, you will need about 30 BTU/Sf to heat it.
Moderately tight average insulation - 40BTU/Sf
Old windy farmhouse 50BTU/Sf (Minimum)
All of those numbers are OUTPUT. You will have to take the INPUT rating
of your appliance & multiply THAT times the efficiency to get the OUTPUT.
So, 2600 x 30 =78K BTU OUTPUT
2600 x 40 = 104K
2600 x 50 = 130K
So if your appliance is 75% efficient you'll need 104K BTU input to get 78K OUTPUT.
Bottom line? Gonna be tough to heat the entire place with one pellet burner.
You may have to close some rooms off or install more than one unit...
Lake Girl
Moderator
Most will recommend looking at the BTUs when deciding on what stove to purchase. What is the average BTUs used by the furnace you have in place now. I think there is a BTU calculator on-line http://www.calculator.net/btu-calculator.html
I'm sure others will chime in...
I'm sure others will chime in...
Thanks. The reason I have been questioning is because I am down to either the p61 or xxv. I know it won't do all of the house but I want it to do as much as I can. So it's 50,000 BTU vs 61,000 - 2600 sq foot split entry home with stove in family room on lower level in corner exterior wall.
Lake Girl is right about looking at your present source of heat. BUT don't forget that a pellet stove is a 'space heater', not a whole house heater. If you are expecting to have a nice, evenly heated house with a pellet stove, you will most likely be disappointed unless your daytime living spaces are central to the stove and only your bedrooms are more isolated. That assumes you like sleeping in cooler temps.
Look at a free standing unit rather than an insert (yes, I have 2 inserts) because fireplaces typically are at one end of the house and not centrally located. In my case, I had no choice. (read that as 'the boss wants them
)..........
Look at a free standing unit rather than an insert (yes, I have 2 inserts) because fireplaces typically are at one end of the house and not centrally located. In my case, I had no choice. (read that as 'the boss wants them
)..........
The bigger the better. You can always turn a big stove down but you can't, or shouldn't, turn a little stove up beyond its rating. Some do and wonder why they shut down or even warp.
Well, have made this recommendation many times here at the forum, Two Stoves
We have three on one floor of a 2400 ft ranch style house in NW Oregon
WE have one stove that's very small (Whitfield Prodigy 2) One large Whitfield and a large Quadrafire
Running one stove hard enough to heat the entire house will result in parts of the house that's close to the stove getting too hot, and the distant rooms will be cold.
Using multiple units and not having to run them hard will give you a more even heat during the cold times, and during the milder weather one stove will suffice.
We use our little stove during moderate weather, the larger one when its colder and then two when its COLD, and possibly add the third (Quad) if needed, or allow it to come on by the stat and take up the slack.
I also believe that two are better, because when you rely on one stove, what do you do when the Snow is blowing sideways and your one stove goes KAPUTT ????
And it will not happen on a sunny day in May, ask me how I know this.
My honest suggestion is to think this over carefully and see if there is a way to install a second unit easily that will give you a good amount of synergism.
My spouse called huge amounts of smack when I set about doing three stoves, but the setup has worked marvelously over the past many years.
The family room has the one Large Whitfield, and the living room (farthest reaches of the house) has the Quad and the little Whitfield.
Yet during moderate weather, the little Whit can keep the entire house comfy.
One thing to consider is, i'ts a great idea not to have to run the stoves "Nuts to the bar" to keep the house warm.
Always go larger than you need for the total, then plan on running the stove in the lower to mid fire settings.
This keeps the thermal stresses on the unit far lower than if you have to run them hard.
The heat exchangers expand and contract a lot during duty cycles, and over time this takes a toll on them, especially if they are being subjected to a lot of heat.
We never run our stoves above the 1 or 2 setting (out of 5)
Just some thoughts.
Ms Snowy
We have three on one floor of a 2400 ft ranch style house in NW Oregon
WE have one stove that's very small (Whitfield Prodigy 2) One large Whitfield and a large Quadrafire
Running one stove hard enough to heat the entire house will result in parts of the house that's close to the stove getting too hot, and the distant rooms will be cold.
Using multiple units and not having to run them hard will give you a more even heat during the cold times, and during the milder weather one stove will suffice.
We use our little stove during moderate weather, the larger one when its colder and then two when its COLD, and possibly add the third (Quad) if needed, or allow it to come on by the stat and take up the slack.
I also believe that two are better, because when you rely on one stove, what do you do when the Snow is blowing sideways and your one stove goes KAPUTT ????
And it will not happen on a sunny day in May, ask me how I know this.
My honest suggestion is to think this over carefully and see if there is a way to install a second unit easily that will give you a good amount of synergism.
My spouse called huge amounts of smack when I set about doing three stoves, but the setup has worked marvelously over the past many years.
The family room has the one Large Whitfield, and the living room (farthest reaches of the house) has the Quad and the little Whitfield.
Yet during moderate weather, the little Whit can keep the entire house comfy.
One thing to consider is, i'ts a great idea not to have to run the stoves "Nuts to the bar" to keep the house warm.
Always go larger than you need for the total, then plan on running the stove in the lower to mid fire settings.
This keeps the thermal stresses on the unit far lower than if you have to run them hard.
The heat exchangers expand and contract a lot during duty cycles, and over time this takes a toll on them, especially if they are being subjected to a lot of heat.
We never run our stoves above the 1 or 2 setting (out of 5)
Just some thoughts.
Ms Snowy
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TimfromMA
Minister of Fire
The better your house is insulated, the more evenly your pellet stove will warm it. My stove is installed at one end of my house in the living room. The bedrooms are at the other end and there's only a 3 degree temperature differential between the living room and the farthest bedroom.
Sniz
Member
TimfromMA
Minister of Fire
My stove is rated up to 40,000 BTU's. Most nights, I run it on 3. The coldest nights I will sometimes set it to 4.
alternativeheat
Minister of Fire
For the folks worried about over heating the stove,I suspect the computerization in the Harmons won't let them overheat.
Did you ever try Stove Temp mode with the P43 ? Maybe stove temp 5 or even 6, feed rate 4 , blower on high. See what happens, because if that blows you out of the room you have it in the P61 will too and then some.
Did you ever try Stove Temp mode with the P43 ? Maybe stove temp 5 or even 6, feed rate 4 , blower on high. See what happens, because if that blows you out of the room you have it in the P61 will too and then some.
alternativeheat
Minister of Fire
No I'm not saying that. What I'm saying is if the p43 cooks you out of the room and doesn't heat the house, then cooking the room more serves little advantage unless you can get the heat out of the room instead of you. Turning the p61 down, which, it will do, leaves you where you are at then, no ? The correlation is more like the P43 on full blast is about like the P61 on level 4.5- 5 actually. But just as a test have you tried stove temp up around 5 or 6 to see if the P43 can do a better job than it is in room temp. In your situation I think Room temp is getting squelched too soon before heat can get out in to the main house. Stove Temp offers a more steady output from the stove. I'm asking if you tried that ?
The XXV is a whole different thing as it mostly blows it's heat by convection, where the P43 and 61 radiate a lot of their heat. They still blow heat too but not the same % of the stoves capacity as the XXV.
Hey, I do only use stove temp- I don't like room temp.
I use it at 4 or 5 and it does seem to move it upstairs. I am getting a fan installed in the main foyer to help move the heat.
You're right, I need to move the heat. Thanks for your input again.
I know the XXV is a diff ballgame but if I can move heat, I am wondering if the xxv will be better than the 43 or if the sure bet is 61
I use it at 4 or 5 and it does seem to move it upstairs. I am getting a fan installed in the main foyer to help move the heat.
You're right, I need to move the heat. Thanks for your input again.
I know the XXV is a diff ballgame but if I can move heat, I am wondering if the xxv will be better than the 43 or if the sure bet is 61
alternativeheat
Minister of Fire
OK, so if you up the P43 to 6 in stove what happens, what is the result besides using a few more pellets obviously ?
CaptSpiff
Minister of Fire
alternativeheat
Minister of Fire
Ya, if you can stand it in the room the stove is in then try more in a couple of hours. Also high fan. Then see how the house does in due time. It takes a bit of time. This is an experiment, so don't be afraid to turn the dial !
I can tell you this about the P61, on high fan it moves the heat out of the room it's in pretty well. However, mine is not in a corner install and I have room around the stove. On those really cold nights when the stove is cranking you don't want to sit right up close to it. We have chairs about 3 ft away and my inclination is to lean out slightly away from the stove rather than towards it..
Lately I've been running in stove temp myself because I think my probe for room temp is either messed up or catching some cool air. In stove temp I get even heat in terms of heating beyond the stove room. I'm happy with that but I do have to dial it up and down by the weather. When the weather warms I can switch back to room temp auto but meanwhile in stove temp it's using less pellets for sure and giving me really nice heat. At one point room temp was not flaring the flame up like is has been for a while now, so I just switched to stove temp and will deal with room temp on next years winter adventure when I've plugged some drafts up around here and found the probe a permanent home..
alternativeheat
Minister of Fire
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