The house has two heat pump ac's. So the second floor has it's own ac in the attic with outlets in the ceiling. That cools the second floor very well. Getting the second floor cool also helps cool the main floor since the cold air falls down the large open entry/stairway.

A two-story house really should have two furnace/ac's. Much easier to control the heat and cooling and get the whole house comfortable.

Also, if one ac quits working there is still one working so you will still have cooling or heat until the broken unit gets fixed.