I am looking to replace window ACs with split units but am running up against a common problem – multiple small rooms that each need their own cooling, but using individual heads will result in excessive cooling capacity and the problems it brings with it.. 3 small (2x 10×12, 1x 10×20) bedrooms, living room , and EI K all need cooling. Metro NYC area.
House is a 1200sq/f semi-splanch (1932 bungalow with 1966 addition). New windows, decent insulation and will be adding 1″ rigid foam board when new siding goes on in the fall. Extensive air sealing has been done but have no measured tests except cutting heating bill over 60% (gas HW / baseboard). Last two summers have been able to cool the entire house reasonably on the hottest days with a single 10.5 K window shaker and box fans to move air around. There is a 9 K minisplit in the MBR, oversized to the point of poor humidity control at temp setpoint.
Considering a single ducted 18 K minisplit that can scale back to 8 K but it would have to go in unconditiioned attic space. Part of that choice is the poor esthetics of wall-mounted units in every room.
My concern on attic install is no shade and even with good ventilation the attic can easily get to 100°F ambient.
Is a ducted minisplit the right way to go or is there a better option?
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