Air to air heat pumps are a pretty straightforward retrofit there. (Including central units with reversing capability; heat pumps don’t have to be per-room mini

Air to air heat pumps are a pretty straightforward retrofit there. (Including central units with reversing capability; heat pumps don’t have to be per-room minis.) In some ways, that style of central heat pump is less talked about because it’s usually a straightforward replacement. Ducts may need to be enlarged in heating-dominated climates though.