Hotblast Furnace

I have a US Stove 1500 Series Hotblast wood/coal furnace. Last year I tried to burn hard coal, and had alot of problems. The only way I could get enough heat to heat the house, was with around 100 pounds of coal in the furnace. I had the ash damper open, and I turned off my forced draft, because someone told me the air above the coals would cool them off. Anyhow is this normal to burn this much coal, is the forced draft a good option for coal, and How long should I expect one loading to last. I was having problems figuring out when to reload with the coal. The one time, I checked it in the morning, and it was pure ash from bottom to top. Any help would be appreciated! I went through a 40 pound bag a day. Is this normal? Thanks

My AHS boiler has the forced draft coming up through the grates. With coal you would want the draft from under the grates and for wood you want the draft from above the grate.
I am not that familiar with the HotBlast furnace. My friend has one and his seems to work great. I would call the company and talk to them. I would think though that you might want to try and see how well it burns coal with the forced draft on. Couldn't really hurt anything.

I think 40lbs. a day is normal on a very cold day I use more than that. I burn soft coal though.