Adventures with Sub-Bit

Adventures with Sub-Bit

PostBy: Kielanders On: Thu Oct 06, 2011 10:35 pm

I'm trying to optimize my burn, being new to Sub-Bit and coal in general.

We've just purchased and moved to a fixer home, the last thing I need to be working on is a proper coal bin.

...or do I?

Does Sub-Bit, or in my case Sub-Bit C, a low grade of Sub-Bit, absorb moisture from the surrounding atmosphere to a great degree?

Right now, we just have a load sitting in the back yard. I know I lose some BTUH with surface moisture, and the temp of the 'cold coal' when I dump it in the fire, but am I going to have other problems because of it sitting outside at present?

Thanks.
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843

Re: Adventures with Sub-Bit

PostBy: murphyslaw On: Fri Oct 07, 2011 12:17 am

Last season I had 3 tons of sub-bit on a tarp next to my house, with a tarp on top to keep the snow out. Burned just fine for me.
murphyslaw
 
Stove/Furnace Make: Hitzer
Stove/Furnace Model: Model 82

Re: Adventures with Sub-Bit

PostBy: Short Bus On: Fri Oct 07, 2011 12:40 am

I see you are in Seward so I asume your coal came from Healy, just like mine, in other words combustable dirt.
I recomend you try and protect it from the weather as it will break down and once it gets small it is hard to burn, not sure why but it probably holds more water in the space between the pieces.
If you keep it out of the rain say in a car port I doubt it will absorb more water it is already over 25% water, see data sheet,
http://www.usibelli.com/Coal_data.asp
This link is broken, either the page no longer exists or there is some other issue like a typo.

You can take a fist sized piece of coal put it on an acurate scale and place it in you house and it will loose about 20% of it's wieght in a week, and it will form shrinkage cracks all over it, I doubt you can make it signifigantly heavier without a hose full of water.
Experiments were done to dry the coal but it just absorbed the water back once the heat was removed, treating with diesel when dry was tried but diesel is now expensive.
These experiment were done by Earl Dunkle and are talked about in the book Alaska's Flying Miner I never actually read the book.
When I hand fed this stuff I would have two coal hods, about three gallons each and as soon as one was empty I would fill it and place them as close to the heat as possible.
If you pile this coal on a fire it will make white smoke, it likes about four cups of coal every 20 minutes, that is a real hassle, so throw a bunch in on a hot fire and if your stove has over fire air you may be able to get the white smoke to burn, or dam near explode, the white smoke is not combustable imediatly but as the fire heats the fresh coal is will be capable of combustion with the addition of air above the fire, in this condition if you open the door to look at your fire it can take a gulp of air and woosh combustion.
With this in mind never completely cover the hot fire with new coal, always allow some flame to exist above the new coal, to help consume the white smoke and keep the people next door happier.
What kind of stove do you have? I see now you have a Harmon TLC 2000, never run one, might be the greatest.
As you burn you will learn. (quote from somone on this forum)
Short Bus
 
Stoker Coal Boiler: Kewanee boiler with Anchor stoker
Coal Size/Type: Chestnut / Sub-bituminous C
Other Heating: Propane wall furnace back up only


Re: Adventures with Sub-Bit

PostBy: Kielanders On: Fri Oct 07, 2011 12:49 am

Thanks to you both. Yes, we get Healy coal as it comes in on the train to the port.

Do either of you have problems with the chunks freezing together in the winter? I am assuming covering it will help.

Can I ask how much you normally burn, what size space you are heating, and what temps you try to maintain?

Yes, we just bought a Harman TLC 2000. It's a nice stove, but having learned what I've already learned in 10 days of burning, it's probably not the best for optimal burning of Sub-Bit. I fault the dealer, as Harman never recommended it for Sub-Bit.

We're cranking through a bit of coal already, and the home is a bit oversized for the stove, but the coal in town is available and affordable - one of the few things in AK that actually is.
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843

Re: Adventures with Sub-Bit

PostBy: Short Bus On: Fri Oct 07, 2011 12:58 am

Running it hard probalby makes it burn better, and possibly more efficient, less vaporization of fuel before combustion.
I have a 40 year old automated stoker under a boiler in the garage, keeps the ash out of the house.
You are going to burn alot of coal, 25 pounds of coal for every gallon of diesel you replace.
If your old furnace burned half a gallon every hour you now need to move at least 12 pounds of coal every hour, coal can become a material handling problem.
And that assumes you get the rated BTU from the coal in your stove. :)
Short Bus
 
Stoker Coal Boiler: Kewanee boiler with Anchor stoker
Coal Size/Type: Chestnut / Sub-bituminous C
Other Heating: Propane wall furnace back up only

Re: Adventures with Sub-Bit

PostBy: murphyslaw On: Fri Oct 07, 2011 1:12 am

Last year I hand made a grate to put in my wood stove. We had 24hr fire for most of the winter. I burned 3 Tons, and kept the house at 72* average. some times it was more, some times less. Loved it so much I purchased a stove. Waiting on delivery now. Cant wait. I am getting a Hitzer Model 82. I heat 2400SqFt build in 81 with original windows and insulation. I dont expect to supply 100% of my heat but a $300 nat gas bill is nuts. So COAL it is. I will be down that way some time in the next month to get some coal. Its still $80/ton right?
murphyslaw
 
Stove/Furnace Make: Hitzer
Stove/Furnace Model: Model 82

Re: Adventures with Sub-Bit

PostBy: Kielanders On: Fri Oct 07, 2011 2:27 pm

Short Bus wrote:Running it hard probably makes it burn better, and possibly more efficient, less vaporization of fuel before combustion.
I have a 40 year old automated stoker under a boiler in the garage, keeps the ash out of the house.
You are going to burn a lot of coal, 25 pounds of coal for every gallon of diesel you replace.
If your old furnace burned half a gallon every hour you now need to move at least 12 pounds of coal every hour, coal can become a material handling problem.
And that assumes you get the rated BTU from the coal in your stove. :)


We ARE burning a lot of coal, and have been for 10 days. We probably average 120 lbs a day, keeping the home at around 62. We're fine with that temp, but it being only October, we're going to need another dump truck load to get us through the winter. I've already tightened-up the home and insulated, and I've been working with the stove settings to try and optimize the burn.

I'm getting fairly nice stove temps with low chimney pipe temps, so what BTUs are available from the Sub-Bit are going into the home. We'll probably get a 2nd stove down the road. It's just the wife and I, so if we have to shut off the upstairs to get us through, no big deal. Still, at these prices and, it makes sense over fuel oil.

Murphyslaw: It was $80/Ton 2.5 Weeks ago, they said there was going to be a price increase soon, but didn't say when or how much.

Did I understand you correctly, that you got 72 degree temps in a 2400 sq/ft space burning only 3 tons in a wood stove with a modified grate? Was that in Alaska, burning Healy Coal? Dude, I have got to talk to you and get some advice!
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843

Re: Adventures with Sub-Bit

PostBy: Short Bus On: Fri Oct 07, 2011 6:37 pm

It would be interesting to know how much diesel it would take to heat your place, I predict five gallons a day if you are going though 125 lbs per day.

Healy Coal 7,500 BTU per pound, Diesel #2 low sulfer maybe 135,000 BTU per gallon, so it's actually about 18 lbs of coal to one gallon of Diesel, assuming similar combustion effiencys, I sincerly doubt we get that kind of efficiency out of our hand fired stoves.

Healy Coal 7,500 BTU per pound, times 2000 lbs, divided by 135,000 BTU per gallon and when you buy one ton of coal for 85$ you displace 111 gallons of Diesel or maybe 400$ worth of Diesel at say 3.60 per gallon.

Pour the coal to it and figure out how to handle the ash.
Short Bus
 
Stoker Coal Boiler: Kewanee boiler with Anchor stoker
Coal Size/Type: Chestnut / Sub-bituminous C
Other Heating: Propane wall furnace back up only

Re: Adventures with Sub-Bit

PostBy: Kielanders On: Sat Oct 08, 2011 12:55 am

ShortBus, thanks for the calculations. Yes, I do have a way to handle ash, and your numbers remind me why I wanted to go down the road of coal. While the Healy coal doesn't have the output I'd hoped, as I didn't see the spec sheet giving the BTUs until after I bought our unit, it is still a good situation, and I'm thankful for that.
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843

Re: Adventures with Sub-Bit

PostBy: murphyslaw On: Sat Oct 08, 2011 1:36 am

The low BTU rating of our coal is why I choose to oversize my stove. I could prob get by with the hitzer 55 but ordered the 82. I want to make sure I dont buy a stove that does not do its job.

What are your stack temps?

What are your stove temps?

Do you have a MPD or a baro?

Clue us in a little on how you are running your stove and we may be able to find some adjustments for ya...
murphyslaw
 
Stove/Furnace Make: Hitzer
Stove/Furnace Model: Model 82

Re: Adventures with Sub-Bit

PostBy: Kielanders On: Sat Oct 08, 2011 3:19 pm

We've been running the stove 10 days, and installed an MPD and Baro-Damper 5 days ago. I'm going to pick-up a manometer soon so I can adjust the Baro properly, as well as stove and pipe thermostats so I can actually do some efficiency calcs.

The stove is undersized for the house, but we can shut off areas at this point to shunt heat within the sq/ft limits of the stove. In this mild weather, it's been doing fine for the whole house. The stove is installed in the basement presently, we're considering a second unit for the first floor.

Heat loss calcs for the whole house are 52 BTUH, give or take a few. I need to upgrade the windows, but I've just fully insulated it with blown cellulose. The efficiency of our hydronic system when up and running should be around 86%.
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843

Re: Adventures with Sub-Bit

PostBy: murphyslaw On: Sat Oct 08, 2011 3:39 pm

Is the rated output of the stove to small for the house? That will make it even undersides with our coal. That is why I went with the biggest stove I could find that I thought I could lift....


I estimate I will burn 4-5 tons this year. As I will also be moving the heat more efficiently. this stove will be on the lower level of my split level home. It has good flow threw out so I know I can heat the upstairs very well. As last year I was pushing the heat down stairs. Once I am up and running I will post pics. Plan on making a trip to seward in a month or so for a load of coal. have other reasons for going down, figured why not while I am there....
murphyslaw
 
Stove/Furnace Make: Hitzer
Stove/Furnace Model: Model 82

Re: Adventures with Sub-Bit

PostBy: Kielanders On: Sat Oct 08, 2011 6:19 pm

From a BTUH standpoint, the stove is rated around 80 BTUH, Our heat load requirements are around 50 BTUH. One problem, I didn't realize how low the BTU output is on the Healy coal prior to our purchasing, which you could attribute to my mistake, but I also would have liked some better guidance from our dealer.
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843

Re: Adventures with Sub-Bit

PostBy: murphyslaw On: Sat Oct 08, 2011 9:08 pm

Whom did you buy the stove from.
murphyslaw
 
Stove/Furnace Make: Hitzer
Stove/Furnace Model: Model 82

Re: Adventures with Sub-Bit

PostBy: Kielanders On: Sat Oct 08, 2011 10:03 pm

I'd prefer not to name them, other than to say that we called a number of dealers on the Kenai and up in Anchorage and The Valley, and all said that they don't sell many coal stoves.

I would say to anyone reading this up here to know your situation and heat requirements, how you'll use the stove, and the issues with burning Alaska Sub-Bit up front, and use forums like these to increase your knowledge base in advance from people that have 'been there, done that'; something we did not do.

But, the issues we're facing aren't horrible, the stove works well - just don't depend on the sales folks to intimately know the challenges related to heating with coal in Alaska.
Kielanders
 
Stove/Furnace Make: Harman & Warm Morning
Stove/Furnace Model: TLC-2000, SF-250, WM843