I have a large output Energyking combo wood/coal add-on or stand alone hotair furnace.
I have used it for 2 years and am happy with it except for when the temp outside is above 20. Unless you want to add wood every 2 to 3 hours (one stick at a time) you will driven outside because it works way to well. This is hooked directly to hot air ducting with proper sized cold air returns and cross flow baffles and works in conjunction with oil . This is all fine .
I have air intake shut as far down as I can get it and use only 2 to 3 year seasoned wood or I would have had a major chimney fire by now . I guess the main problem the unit is just too efficient with wood fire. I have a 28 foot 6 inch SS insulated all fuel chimney. There is no barometric control installed( was told not a good idea if burning wood and chimney catches fire as it would create a super fire in pipe with the added air(this made sense to me). I was told with coal I need to have a chimney installed draft air regulator which is ok as I could block it if I used wood . I have baffles in grates that need to be switched to COAL so air is from bottom instead of top for wood.
My question is can I safely control a coal fire by restricting air intake as long as chimney is always at full flow with only a flapper type barometic draft control? Some call it an offset pin damper. Was told I must have this to allow fumes to always have a way up chimney.
Will I be able to control this fire better than with wood? I wll buy anthricite from a local dealer by ther bag to try it. He has given me his take on coal and he burns a stove in his home and a huge one in his shop and a smaller "round oak" stove.
What size coal should I start with? Pea or Chesnut? My furnace has shaker grates for coal and holds either 90 or 120 pounds of coal.
Also am afraid of coal because I know a family that had a stove explode and killed 2 of there children years ago but many oldtimers swear by coal. I have burned wood for 40 years . Thanks TJV Sorry about the typos bad cut on my finger bandage is in way hits extra keys.