maple1
Minister of Fire
40 F is usually my line.... house maintains 60 - 65 F on it's own when it's 40 F outside, unless it's been bitterly cold, windy, etc.
An over night fire in the centrally located chimney insures radiant heat for quite some time, a win / win for me.
Burning at those temps is probably one of the reasons you've gone thru the coal & firewood that you have.
If it were me, I'd be saving for the colder temps of Jan / Feb / March. Sucks to run out. Been there, done that.
Heck with that - if it drops below 70f in here, I'm lighting a fire. I didn't invest in these wood piles just for decorative purposes, comfort is the name of the game.