Thx....I think we need to do something about our A/C...even tho we only use it for a few weeks maybe, in summer. (You must be somewhere hotter). Our Master Bedroom becomes too hot to sleep (upstairs) while the downstairs is freezing...I bought a portable (floor type) A/C for the MB, but it is loud and not great. But, First, I want the carpet out, and wood floors in there...I HATE wall to wall carpet!
Our engineer son lives in a two story home. He had the contractor put two ac/heating units on the same floor and outside fans on concrete pads outside their home.
They use AC about 6 months a year. He has a Nest thermostat for each unit. He can control the Nests with his smart phone.
During the hot time of the year about 3:30 to 5 pm, he turns on the AC for the top part of the home. Besides big wide stairs there are a couple of open gallery type areas from the top floor to the ground floor. So the cold air goes from the top floor to the bottom while cooling the top floor and starting to cool the ground floor. This keeps the teens out of the first floor where the tv and kitchen are.
He and his wife enjoy 80 ish weather during the warm season. Often when they get home from about 5:30 to 6 pm. There is no need to use AC to cool their bottom floor. By bedtime, they usually have a sea breeze to keep the cool upstairs BRs cool.
This reverses in cool to cold weather. He turns the heat on the ground floor and as heat rises, their BR areas warm up.
Their utility bills, when compared to neighbors with the same floor plan, who think this is too much effort or everything on a single floor, those neighbor’s utility bills are double to triple what our son’s bills are.
Our closest neighbors set their thermostat at 76 year round, and their ac or heating unit is basically on 24/7. Their bills are 4-5 times higher than ours for a smaller home.
My wife and I walk by their home about twice a day on our walks. Their AC or heating system is going, and the temp is great outside.