How to Heat & Cool 3 Rooms via Mini Split(s)
We are building a house in Paso Robles, CA. Central CA Coast technically, but about 20 miles inland (Zone 3C per the map). It get’s 115 deg F often in the summer and in the 20’s in the winter, though never for long.
The East wing of the home will act as vacation rental, though on a per room basis. What the French call a “Maison D’Hôtes”
So we three essentially identical rooms side-by-side, about 300 sq ft each with 10 ft ceilings. Visitors will want to be able to control their own heating and cooling needs.
The home is well insulated. Unvented attic and crawl space. Code insulation in the walls and below roof deck. Also 1-2″ of polyiso on the outside with an air gap between the foil sided foam and the metal siding/roofing (white/gray).
My first thought was three small mini split systems with wall mounted indoor units. But for aesthetic reasons my wife prefers ceiling cassettes or concealed ducted units. I am attracted to a 3-zone system with a single outdoor unit. But I am concerned that the three indoor units may not respond in the same way as three independent systems. For example, would all three indoor fans come on when one of the rooms called for cooling? I just made that up, but it’s in my head that I have read about issues like that.
Can anyone clarify? Would a three-zone system behave identically to three independent mini split systems?
Thank you – Gustave
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