I've had 3 weeks of steady coal burning now. I started primarily burning anthracite at first and have bounced back and forth between that and bit. In my part of the country we have had some wild temp swings. From 60s to single digits. That issue alone is probably enough to not make this a very accurate assessment of the burning characteristics of the two types of coal.
With that said, here are some thoughts from my experiences.
There are a couple of things to keep in mind as you read through my musings; A) As many of you probably already know, I have crazy high draft in my chimney when I'm burning. I have a large double flue chimney that goes up through the interior/center of my house and out through the center of the roof peak. B) I burn KY bit coal in fist to football sized lumps. This stuff burns easy and hot. I'm not sure whether it's high coke button or low coke button coal. Berlin is the expert on bit coal and he gave me the low-down on it once and now I can't seem to find it. All I know is it is easy to burn in a US Hotblast furnace.
As of now my opinion of anthracite coal is somewhat mixed (TSC Kimmels). The stuff is very stable and burns for long periods of time without tending at low temps. It doesn't smoke or smell. (as a side note, it puts on quite a show after ignites and when it starts to get hot. The secondary air feeding over the fire through my added tubes is awesome to watch, that alone is almost enough to burn anthracite
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The grates in my stove are rocker grates and are not the best for shaking down anthracite effectively in my opinion. Lightning, I know you and Ashley have a great relationship and you have your shake down down pat but I can't seem to get the hang of it. If I shake only, I cannot clear enough ash. If I run a longer poker through the coal bed to clear it, it seems to upset the burning anthracite and cool it off. Then when I add new fresh coal it takes FOOOORever for it to ignite. I mean like an hour or so. It can be glowing like a neon sign underneath and if you have to add 25 or 30lbs, it just takes forever. If it's cold outside the house will start to cool off waiting for it to fire back up again.
I leave the ash pan door about a 1/4 of the way open and the load door open 3" or so trying to get it to ignite. I've covered the baro with foil and even tried putting a small fan close to the ash pan door blowing some air under the coals to see if that might help but no luck (actually the fan seemed to cool off the glowing coal instead of making it hotter). There seems to be a fine line of when it's best to reload it. If you let it go to long, while it makes clearing ash easy there isn't enough heat for it to easily ignite. If I try to soon, clearing the ash is a pain in the a$$ and it upsets the burning ant coal. That cools it off making it again, difficult to ignite...
Another thing that I've noticed is that I have to burn the anthracite in the 450 to 500 degree range to keep my house warm when it's cold outside (20s or below). Consequently I can easily burn 80lbs of fuel in 20 to 24 hours.
As for bit; bit starts easy, warms quickly and is easy to adjust for temp. It holds hot coals for about the same time as the anthracite does and all you have to do is throw 25 lbs on and it is raging again in 20 minutes or so. I can reload when I get home from work and heat the house up very quickly if it's cooled off.
As I indicated above the anthracite fire is beautiful to watch when it ignites after loading. As for the bit fire, If I have all the secondary air open and don't start backing down the primary controls relatively quickly, the fire box turns into one spectacular fire ball. It's kinda cool too but a little scary...
The shake down is very easy with bit. Rock the grates a half dozen times, run the long poker down both sides of the fire box, shake again and the ash falls right out. Done... The bit coal doesn't seem to mind it if it gets stirred up a little. It will actually break open some of the hot coked coal and heats up the fire box very quickly.
One other benefit to bit is it's about a 2/3rds of the price.
Bit has drawbacks too - it smokes like a freight train when you reload it for about 10 to 15 minutes and smells pretty strongly for about 45 minutes. But after that there is very little smoke or smell.
Anthracite will keep a more consistent temp in the house but to do that it seems to use more fuel.
With bit I can let the house cool off when we are not there and then quickly heat it up when we get home.
I actually did burn the 2 fuels at the same time. There were some interesting things about that I want to experiment with some more before I give my thoughts on that.