Question for you pros. If all 4 of my bedrooms upstairs have returns in each room, is it more economical/efficient to heat/cool them with the doors opened or closed?
I was wondering because I can picture all my cold air conditioned air coming out of the supplies of my bedrooms and sorta cascading down the stairs. Does it make sense to close the doors when the system is either heating or cooling, or do I just leave them open unless everyone is sleeping?
Does it even matter?
Thanks in advance !