Hello brent, your basic math and physics is right, but you are neglecting a major factor.
These stoves give off huge amounts of radiant heat. I would say that at least half the heat output from a Keystoker is from radiant heat off the front, top and sides of the stove body. I'm not sure how you would calculate this heat output, probably have to create a test cell to run the stove in with instrumentation.
As for the Keystoker or any other model from MOST, but not all stove makers, they are advertising the input BTU's from a fully burning stoker, with hot coals falling off the end of the stoker bed.
You have to multiply the BTU input by the effeciency of the stove. If you are only going to count the heat from the 265cfm blower, and not count the radiant heat from the stove body, then I'm gonna guess the effeciency is going to be less than 40-50%.
We have had numerous threads about lack of heat output from stoves placed in basements, where all the radiant is wasted trying to warm up the walls of a masonry basement, and the warm air distribution fans are pulling 55* air off the concrete floor and trying to warm it effectively and send that up either the stairway or warm the floor above the stove. This just doesn't work.
These coal burning stoves are NOT furnaces. They are heating appliances meant to be put in the living space where all the heat, radiant and convective is given off to the living space.
If they were furnaces, they would have cold air return boxes, filters, hot air outlet pipes, and most important INSULATED sides and top, so the radiant heat is not lost to the basement, but is added to the hot air output.
So the average stove is rated with BTU input, and where and how the owner places the stove will for a great extent determine the heat output from the appliance.
Last edited by LsFarm
on Sat Feb 24, 2007 1:47 pm, edited 1 time in total.