Coalpail.com Forum

I am going to do the opposite of the other writer. I am switching from a Ravelli 100 Classic Pellet stove to a 105 Keystoker. The Ravelli just doesn't have the horsepower to heat my home. In saying all this I haven't totally ruled out the a Harman P68. In rating coal and pellet stoves........is the 105 (in the Keystoker) and the 68 (in the Harman pellet) input or output ratings? I am more concerned with the Output btus.......I wanna know how much heat is coming into my house. My Ravelli is rated at 48k input btus and i think that translates to roughly 35k btus output into the house. Also, if I go coal, i want a direct vent coal stove. Is a direct vent coal stove about as load as a direct vent pellet stove ( all fans running and such)? Any answers would be greatly appreciated. I am not doing this switch until summer....so ive got alot of time to figure this out. Thanks

Homeskillet

Heat output does not correlate at all well to manufacturer ratings. It does correlate well to consumption and a knowledge of efficiency (which will be less than the idealistic figures touted by manufacturers). All of the heat energy is in the fuel. No heat energy exists due to magic.

I would initially assume a real world 70% efficiency for both appliances, ignoring manufacture boasts of 80% to 90%.

Pellets deliver 7,825 BTU's per pound X 70% efficiency = 5,478 BTU's per pound as delivered heat output
Anthracite delivers 12,250 BTU's per pound x 70% efficiency = 8,575 BTU's per pound as delivered heat output

Examples for the same house on the same day (or under identical temperature conditions) over the same 24 hour period:

1) Pellet stove has burned 100 lbs. in the past 24 hours
100/24 = 4.17 lbs. per hour burned
4.17 lbs./hr. x 5,478 output BTU's/Lb. = 22,843 output BTUH (or average BTU's per hour delivered into the house as output)

2) Coal stove has burned 64 lbs. in the past 24 hours
64/24 = 2.67 lbs. per hour burned
2.67 lbs./hr. x 8,575 output BTU's/Lb. = 22,895 output BTUH (or average BTU's per hour delivered into the house as output)

For this example, if a pellet stove is burning 100 lbs. on a day where a coal stove would burn 64 lbs. they have both heated your house at the exact same output rate of about 22,870 BTU's per hour (or BTUH), when allowing for rounding error.

The main key to understanding real maximum heat output potential is to know for both types of stove precisely how much fuel it is capable of reliably pushing onto the stoker per hour when running full out, with combustion air at the correct setting for a quality burn. After this the only remaining variables that matter much revolve around efficiency (in its various measures).

That about sums it up. Well done Larry.

Regarding the noise...double check the cfm ratings of the fans on both units. I would guess the fans on the coal stoker may be louder since I think they have higher cfm than the pellet stove fans.

or burn a second pellet stove and gain a redundant heat source :>)

Kind Regards
Sting

Sting wrote: ↑

Tue. Mar. 13, 2018 9:35 pm

or burn a second pellet stove and gain a redundant heat source :>)

Kind Regards
Sting

Well said.

But in this case the OP is counting his watts one by one in a solar off grid home.

It may be that a second pellet stove can still measure up to his task.

Thanks to all. A second pellet stove would definitely work. Ive thought about that scenario..but I am trying to avoid it. I dont want 7 tons of pellets setting around when I can get my with 4 tons of coal...or whatever the case may be. Coal dust versus pellet dust kinda scares me. Pellet dust is bad enough. I hope that buying oiled coal will keep the dust at bay for the most part

I've recently switched from pellets to coal. I've been burning coal for only 25 days. Hands down coal is the way to go. My pellet stove would have burned approximately 25 40 lbs bags of premium wood pellets at a cost of $165 with an average temp of 70-72 degrees. I bought a ton of coal and have used @ 25% of it. figuring high - Ill say I've used @ 25 lbs a day or @ 625 lbs of nut coal at an average temp of 78-80 degrees ( that's where I like it) for a cost of @ $77. So far I've heated my house warmer at half the cost.
As for the dust I don't think its much dustier than the wood stove it replaced. To compare it to the pellet stove, definitely a little more dusty but then, it is a hard comparison. Pellet stoves have to be vacuumed out. I can't say how much dust blew through the vac into the room.

Another happy convert ^^^

homeskillet wrote: ↑

Wed. Mar. 14, 2018 9:40 am

Thanks to all. A second pellet stove would definitely work. I've thought about that scenario..but I am trying to avoid it. I don't want 7 tons of pellets setting around when I can get my with 4 tons of coal...or whatever the case may be.

My initial guess is that 4.5 tons of anthracite coal equals 7 tons of wood pellets. It would definitely be a space saver, as 4.5 tons of coal would take up a bit less than half the space of 7 tons of wood pellets. And if really pressed for space, coal can be stored outside.

Find a harman DVC, it is the best direct vent stove on craigslist. You will be happy.

If this is for an interior space, non basement harman DVC is the way to go