coaledsweat wrote:According to Axeman-Anderson, a ton of anthracite starts with 240# of useless ash (12%). The anthratube will waste 60# of that ton in unburned coal (3%). It also points out that 200# (10%) goes up the chimney as wasted heat. That leaves 1500# actually heating the house (75%). I would think that other stokers would be a little less efficient. That adds up to about 15% or 15 # per hundred in to ash out w/unburned coal as the "best case" scenario.
I will add that the "Yanche Report" (Bureau of mines) shows it to be slightly more efficient than advertised.
So unburned % in the very best case will run 3% or higher, the average stoker may run @ 4-6% (4-6#) unburned coal in the ash.
OK, I take back all the complimentary things I said about admin! Here's what I can recollect about the massive deleted portion of my earlier post:
First, referring to the above quote, I posited the question whether I reasonably may infer that, if I'm running at about a 20% weight ratio of ash-to-fuel, I may consider that a pretty reasonable fuel consumption efficiency, even if my ash looks like it contains a fair amount of unburnt coal. (The ash number is a guess; I weigh my fuel in but not my ash out.)
Then I admitted that, at the beginning of the season, I tried to strain out the unburnt fuel from the ash. But not for long!
* * * * * * *
Finally, I waxed along a season-ending theme of the value of this forum in pooling and preserving a body of experience and expertise on the subject of coal heating, which it is my impression was in danger of practical extinction. I've found it interesting that old-timers often show what seems to be instinctual familiarity with the parameters and rhythms of coal burning, probably owing to having grown up with coal furnaces. Yet it seems largely lost on the boomer generation, where more "convenient" fuels have been nearly universal. So here we're trying to collect and preserve what we can of what's gone before, in addition to adding what we can of what new technology can bring to both the efficiency and user-friendliness of coal heating.
Then I thanked the forum administration for providing a place to do all this.
And now I've retracted all that. :footballhelmet: