There's been some discussion about boiler sizing, and I'm feeling a bit defensive since mine is so small compared to everyone else. Boilers, folks - get your mind out of the gutter! Part of my theory is that big enough is good, but bigger isn't always better. I sat down with a glass of good bourbon and crunched the numbers for my last heating season from October 21 through April 14. My boiler was burning (defined as a water jacket temperature above 140 degrees) for an average of 51 hours per week, with a maximum of 86 hours. That works out to an average of 7 1/2 hours per day and a peak of 12 1/2 hours per day. It burned for a total of 1282 hours, and burned 4.5 cords of wood. It's an EKO 25, which is rated at 80,000 BTU/hr. By my calculation, it actually produced an average of 63,000 BTU/hr and 18,000,000 BTU/cord. The time between fires is determined by the size of the storage tank. If I had a larger boiler, I think I would have had more fires, but each one would have been shorter. Does that make sense? How does this pattern compare with what other people are doing?