How many BTUs to buy

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FiredUp

New Member
Hearth Supporter
May 22, 2008
17
central mass
Hi-

We're new to the pellet stove game. Decided to buy one to help defray (by a lot!) our HHO costs for the coming heating season. We're going with a Harman because we've found a very good dealer. My question is: My house is approx 1800 sf; one story with a great room (lr, dr,k), and three bedrooms farther down a hallway. My stove will be in the lr. Am I better off going with theP68 (68K btu), the 61A (61K btu) or will the XXV (50K btu) be enough to heat the house? I plan to turn on the oil furnace when the temp drops real low to prevent frozen pipes. Also I've heard complaints about fan and auger noise. How about those issues with the above named models? Any help you can give me will be greatly appreciated!!
 
My local Harman dealer came to my house (no charge store is about 20 miles away) to help me decide if the P61 would be sufficient for me or the p68. I don't have a great room, more of a closed off floor plan but decent flow between downstairs rooms and was told the p61 would be sufficient for heating my ground floor. Guess, my point is to see if your dealer would pay you a visit to help you make the right choice for you.
 
There is a lot going on with a pellet stove. It would be best to take your time and learn about how they operate. The design of the Harman's is time tested and works well. However, there are other brands that are quieter and more efficient. You might also take a look at Enviro and Quadrafire stoves before finalizing any decision. The Quad Mt. Vernon is exceptionally quiet and efficient. Go at a really quiet time (morning, weekday) and listen to the stove at various speeds through an entire cycle or two.

As to stove size, how leaky is the house? What is the boiler size (btus output)? How much oil did you go through last year? It sounds like your preference would be to run a stove on medium speed to keep the noise down. If so, getting a slightly oversized stove could be a good plan.
 
BeGreen is right about some of the factors in deciding what size to buy. A well-insulated and closed-up 1800 sq ft house would take less heat than an old, drafty, uninsulated one (like mine). And how warm you expect to keep the house makes a difference. How much oil you used before is a good indication. I think oil is about 140,000 BTU/gallon ?

Another note - if I'm not mistaken, the BTU ratings of the stoves are how much BTU input they can take, NOT output. My Harman XXV is rated at 50,000 BTU/hr, but at say 80% efficient it's really more like 40,000 getting into the house.

As far as noise, I haven't found mine to be the least bit offensive. Yes I can hear the fan and the auger, but I often hear heating systems (whether they be furnaces, forced air, or whatever). To me the sounds coming from my Harman are not excessive and not offensive. That's my humble opinion :-).
 
BeGreen is right about the Mt Vernon. The convection blower speed is user-adjustable. The "normal" setting is quiet enough for me, and the "quiet" setting would be suitable for a library. Its auger noise is nonexistent. The loudest noise by far is its self-clean cycle, which is still quieter than a laser printer.

BTU ratings are simplistic - they're just a measure of how many pounds per hour they'll feed, and BTU content of pellets can vary widely. That and efficiency are big factors in determining usable heat output. I think bigger is better - if you buy a big stove and don't need all its capacity, it's better than buying a smaller stove and not having enough. Larger stoves tend to have the advantage of larger hoppers which means less work for you. Also, more BTU output will bring a cold room up to temperature faster. Your decision will have to consider how you'll actually be using the stove so YMMV and all that.

BTW I think Harman makes a great stove. Neither it nor the Mt Vernon will make nearly as much noise as an oil furnace. If you found a "very good dealer" I think that's reason enough to stick with the Harman.
 
Thanks so much for all your advice everyone! :-) We set up an appt. for a rep/installer to come out next week to take a look and give us the lowdown. Now I've got another question: how much room does it require to store pellets? We have a screened in area of patio attached to the house and we thought about lining it top to bottom with plastic and keeping the pellets in there. It's about 8'X 13'. About how much could we reasonably expect to fit in there? Would it be an OK storage space? Thanx in advance.
 
A ton of pellets seems to be about 4x4x4.5 feet or about 75 cubic feet? That sounds like a fine place to store pellets - if it is on a framed floor, make certain to consider the weight.

Also, as far as stove sizing goes, keep this in mind. The average pellet user seems to burn about 2 bags in 24 hours in colder weather. That means an input of a little over 3 pounds per hour - input of 25,000 BTU or so. When you think of it this way, you'll understand that the maximum heat output is usually not of as much concern. It's like buying a car that does 100 MPH, when you are only going to do 70.

In short, the XXV certainly sounds like it will do the job easily. There is always that few days when NO amount of heat or pellets seem to do the job, but a "space" heater like a pellet stove should be thought of as a supplement...not as the central heat.
 
Webmaster said:
A ton of pellets seems to be about 4x4x4.5 feet or about 75 cubic feet? That sounds like a fine place to store pellets - if it is on a framed floor, make certain to consider the weight.

I would say that storing the pellets on a frame floor is questionable. At the dimensions you give, which are pretty close, that's a floor loading of 125 lbs/sq ft. Especially since there may well be a few tons stored all beside each other, that sounds prohibitive for anything other than a concrete floor right on the ground, like a cellar floor or patio on the ground, or a reinforced institutional concrete floor above grade (like in a hospital or factory), which most folks don't have at home. Most residential floors I think are rated around 20 - 30 lbs/ sq ft. That's the average they'll take over an area, though they'll take more in a small area, like a person standing there or a sofa leg would be more in a small area, but not the kind of area that pallets of pellets will take up.
 
Thanks again for the quick responses. As far as the floor goes it is a solid cement slab on the ground, so it should be perfect. We'd like to buy 3 or 4 tons and store them there - before the price goes up!!! The next question is what type of pellets are best? I know that the premium produce less ash, but is there a specific kind of wood or a particular brand of pellets that is better than the others? Once agin, thanx in advance! It's great to be able to tap into all this knowledge. I'm really glad I found this site!
 
FiredUp said:
...what type of pellets are best? I know that the premium produce less ash, but is there a specific kind of wood or a particular brand of pellets that is better than the others?

Hey FiredUp,

This is strictly my opinion and my brief (only 4 months) experience, but I love the Energex pellets. I have 6 tons of them in my cellar waiting for next winter !! You can check out their website (I think it's energex.com). They're made in Canada, are all softwood (higher heat content), are the right size (they look like rabbit food, and feed right in, not like pretzel sticks like cheaper pellets, that can bridge over and not feed in), and my stove has never gone out with them (uniform dryness). The only other pellets I've used were from Walmart - a little cheaper, but bridged over, went out, and made LOTS of ash. A friend used Lowe's pellets, and they ran okay for him, but for about a week his stove wouldn't run last winter. I know others have had better luck with pellets like NEWP and a few others.

I guess it depends too on what your needs/wants are. Some folks are home all the time and don't mind tending a stove that goes out periodically. I have an empty house for most of each day, and want dependability. I also prefer pellets delivered to my cellar door, while some folks don't need that. (That's more of a dealer issue though.)

Good luck FiredUp !!

Newpelletstove
 
Thanks for the advice! I keep hearing from people that hard woods are preferable, but obviously you don't agree. Do softwoods burn faster and create more ash than hardwoods?
 
FiredUp said:
Thanks for the advice! I keep hearing from people that hard woods are preferable, but obviously you don't agree. Do softwoods burn faster and create more ash than hardwoods?

Hey FiredUp,

I haven't burned a high-quality hardwood pellet, so I can't say, but I can say that the Energex pellets don't make very much ash at all in my stove. No ash complaints here. My ash bin might be filled after burning a ton.

As far as softwood vs. hardwood, here's something from the Energex website:

"Wood pellets, whether made from hard or soft wood, have approximately the same density therefore similar burn times. Softwood pellets have the added benefit of clean burning resins that ignite for the higher BTU value."

Here's another thing from their site:

"AVERAGE 9,000 BTUs/LB. Most others average 8,000 to 8,500 BTUs. With a higher BTU, you burn less fuel for the same heat output."

I don't mean to sound like an Energex salesman, lolol, but these are some of the reasons I feel comfortable with the Energex pellet, plus, of course, and most importantly, the fact that I've had nothing but dependable feeding, burning, and low ash from them.

Take care bud.

Newpelletstove
 
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