I'm envious, only what, 50-100# in 4-5 days??
I fired up the boiler last night, I've burnt at least 50-80# of coal in the last 24 hours. But I'm heating this sieve diguised as a farmhouse.
Just getting the water in the boiler and system up to temp consumes about 20-30# of coal, once it is hot, then the house pulls a lot of BTU's out of the system, and of course today is laundry day, so all the cold water fed to the hot water tank is going through the second heat exchanger. The water entering the heat tank is at 150*, the tempering valve brings it down to 120* on the way out of the tank.
The house is at a toasty [for me] 68-70* .
Love this coal heat.