We can not close the upstairs off from the downstairs, the upstairs set at 78 degrees and downstairs at 77 except for 8 hours at night at 75 degrees, we hour ave a fan at the top of staircase running night and day to circulate air and ceiling fans running with one oscillating fan in bedroom. Do you have any more solutions to keeping the home comfortable but keeping electric usage down, or suggestions to help. The upstairs is not being occupied but if we keep it hotter, our downstairs unit will run all the time. Any suggestions or recommendations will be useful. What do you suggest we save enegy?

I would experiment further. If the upstairs isn't one big room, close every door to every room and open the windows an inch, and find a spot somewhere near the top of the stairs to install a rigid foam barrier made of 4' x 8' x 2" panels. Then turn the thermostat off again. Yes, some heat goes right through the ceilings downstairs, but most goes up the stairs. You might even be able to make a 'hatch' at the top of the stairs, if there are walls and ceiling around that area.

I spend time each day opening windows at night, then closing windows and pulling down shades before the sun hits in the morning, and I use fans only, no AC. That's because I'm cheap and because I am sort of an energy saver nut.