"Larry Bud" wrote:

1/6/05-2/5/05 -- 30 days, 43.9 heating degrees PER day, 12.433 ccf/day
1/6/06-2/3/05 -- 28 days, 30.54 heating degrees PER day, 8.1 ccf/day

You are probably talking about "degree-days," ie degrees TIMES days vs
degrees PER day. A degree-day is a 1 F temp diff maintained for 1 day...
43.9 DD would be a temp diff of 43.9 F maintained for 1 day.

I should also note that I would estimate approx 0.65 ccf/day for non
furnace related gas usage...

That may not matter in January, if the heat ends up in the house.

If you know your furnace efficiency and therms/ccf and indoor electrical
energy usage, you can estimate the thermal conductance of your house. For
instance, with an 80% furnace and 1 therm/ccf and 600 kWh/mo (68K Btu/day)
of indoor electrical use, the first record would correspond to a house with
(100Kx12.433/0.8+68KBtu)/43.9F/24h = 1540 Btu/h-F and the second would make
(100Kx8.1/0.8+68KBtu)/30.54F/24h = 1474, both being quite high, compared to
a new energy-efficient house with a thermal conductance of 200-400 Btu/h-F.

Nick