Unburnt coal - Quality problem?

I've been having issues with unburnt coal. Should the coal burn completely to ash? If left unattended I'm always left with a small layer of unburnt coal. I'm burning Blaschak...clean with very little fines. Ash seems chunky, not chalky! Does brand affect quality? Any advice would be greatly appreciated!

where is this small layer located?



Eric

Sorry, I should've been more specific . I have a coal chubby with a suspended fire pot. The unburnt layer of coal is left on the grate.

tcalo wrote:

Coalfire wrote:where is this small layer located?

Sorry, I should've been more specific . I have a coal chubby with a suspended fire pot. The unburnt layer of coal is left on the grate.

What do you mean left on the grate.


Left on as chokes the air flow? or when you leave the stove burn out?


Eric

I let the stove burn out and there is unburnt coal left on the grate. I assumed the coal would completely burn to ash.

Coal will not burn to ash when allowed to burn out. Coal always needs new coal to complete the burn of previous coal as is goes through its burn cycle. We are burning stone not trees.

2001Sierra wrote:Coal will not burn to ash when allowed to burn out. Coal always needs new coal to complete the burn of previous coal as is goes through its burn cycle. We are burning stone not trees.

Good to know. New to coal so I'm still learning. I was loosing my marbles trying to figure this out. I burn both wood and coal and thought maybe the wood ash was choking the fire so I switched to strictly coal for the past few days. I haven't had a problem when I have a continuous fire burning, but once the fire gets too low it seems to peter out leaving an unburnt layer behind. I've been experimenting with the MPD to see if it helps.

Keep the faith, you will do well

tcalo wrote:

2001Sierra wrote:Coal will not burn to ash when allowed to burn out. Coal always needs new coal to complete the burn of previous coal as is goes through its burn cycle. We are burning stone not trees.

Good to know. New to coal so I'm still learning. I was loosing my marbles trying to figure this out. I burn both wood and coal and thought maybe the wood ash was choking the fire so I switched to strictly coal for the past few days. I haven't had a problem when I have a continuous fire burning, but once the fire gets too low it seems to peter out leaving an unburnt layer behind. I've been experimenting with the MPD to see if it helps.

Fire should not get to low, if you are on a regular shake and refill schedule. Yes the MPD will keep more heat in the stove so you can use less coal. Do you fill the stove all the way? what are your shake and reload schedules?, Hows hot do you run the stove?

You will get the knack of it


Eric

I do a lot of burn out/restart cycles with a little hot water boiler. I always have a layer of partially burned coal on the top of the ash after the burn out. When I do my shake downs I decided to get out the ash but leave as much of the partially burned coal on the grates before I do my restart because I hate waste. I build my new fire on top of that residue. I don't get crazy about picking out the partially burned stuff out of the ash, just what is obvious. Once the fire is re-established that partially burned stuff gets burned and passes through the grate during routine shake downs, minimal waste. Unburned residue on burnout is just the nature of the beast.

I get some chunky ash as well.