I'm in love - with sub-bit

Finally fired up my new boiler - a Biasi 3wood. I burnt wood for the first few days and quickly confirmed this unit is not suited to wood-burning, despite its name. I got 12 ton of sub-bit thermal coal in chunks from fist to volleyball size. I pitched a pail-full in and waited for the smoke show which never happened. This stuff burns with a little wisp of smoke and that"s it. Just the typical tarry coal smell. It was easy to light. I was surprised at how "cool" the fire was, like it puts out only as much heat as you need. 2 loadings a day is plenty but I have to remove the ash twice a day also. There's no clinkers either, just fine ash like wood ash that drops through the grate. So far, so good and at $40/ton the price is right.

I've also burnt peat in this boiler. I cut some from the swamp behind the house this summer and dried it out. It burns hot and fast then coals more like wood. Its so light though it would take a lot to heat for the winter. Fun to play with though and free/easy to get.

I have Sub-Bituminous "C" coal, caricterized by lots of volitals, initial smoke.
Sounds like you have Sub-Bituminous "A" coal, caricterized by low quantitiy of volitals.
http://www.miningbasics.com/sub-bituminous-coal
I wish I had a better link,
Any chance you can find out more information on your coal?
It sounds great, and there is no chance I will make the trip to get some, just courious about the official type.

it sounds like you have some good sub-bituminous coal there....and you have the right size too....with sub bit coal the bigger the lumps your firebox can handle the better(less smoky) burn you will get.

the main local supply of coal here is a sub-bit coal and its common knowledge that if you burn the larger size in a coal stove you don't get any clinkers....high ash percentage is a downside of some sub-bit coals but is a small price to pay for cheaper heat

I think its "C" grade as well. Maybe the larger size helps the burn? Here are the specs:

BTUs per pound : 8000 to 8500
Ash Content : Approximately 8%
Sulphur : less than 0.05%
Moisture : 20 to 25%

The ash removal is due to the only thingI don't like about this boiler - the ash pan is like a tin lunch tray. I think I'll get a tinbasher to make me a deeper one.

I have similar numbers but lots of ash.
Burning in an underfed stoker my ash is becoming clinker, much better in my situation than ash.