On Feb 13, 12:46 am, "Donna Ohl, Grady Volunteer Coordinator"
wrote:
Does this calculation look right to you?
240 therms/year * 1 year/41,045,000 btu * 100,000 btu/1 therm = .58

The part of the math that escapes me is why this calculation uses 1,000
times the BTUs per year than the previous calculations. Any idea?

Why do you use 41,045 BTU in one calculation when you have the EF in
hand and 41,045,000 BTU in the reverse calculation when you're trying
to determine the EF?

What is this "magic" number 41.045 anyway?