Can ductless air conditioning+heat pumps work well on floors that have doors closed?
With the doors closed and no evaporator in the room how is the cooling going to get into the room. In short it will not work with natural flow and the doors closed. On my 1930's home we have a 3 zone currently. The living room and the kitchen/ dining and the the master each have a unit. The other 2 bed rooms only get cooling / heat when the doors are open but since these only get used when relatives or grand kids are here we have not put a second unit in. I may add a second unit on the other side of the house for the 2 bedrooms and a small office but at this point it is not needed because we heated with wood for so many years we are used to having our doors open and that saves because we still use partial wood most of the winter as I am getting lazy LOL.