Location: US, NYC. I want to improve the air conditioning setup for an apartment in a 2-family house. Current situation:
- 200 sq ft master bedroom, horrible old through-the-wall AC on a dedicated 20A 120V circuit
- two 80 sq ft bedrooms, currently without air conditioning, each have dedicated 20A 120V circuits for AC, but the window shape is unfriendly to normal window ACs
- sitting/eating area connected to kitchen and hallway, around 350 sq ft total, horrible old through-the-wall AC on a dedicated 20A 120V circuit
- basement containing washer/dryer on a 240 V circuit.
My idea was for a multizone mini-split AC with a single outside condenser and 4 indoor units - one in each bedroom, and one in the sitting area. I realized I would need 240 V for the compressor, but thought that could be gotten from the basement. However, after looking at the specs for models on the market, I see what looks like two problems:
- the multizone indoor units for which I was able to find specs seem overpowered for the two small bedrooms: for example, Mitsubishi doesn't advertise any indoor units under 6000 BTU, while various online calculators suggest 4000 BTU for such small rooms
- the multizone mini-split systems for which I have been able to find specs seem to require 240 V for indoor units, which I think implies a very expensive and very disruptive wiring job.
Is my assessment of the situation correct? What is the right way to set up a mini-split AC for a home with small bedrooms? Is a separate AC per bedroom the better way to go? (Alas, four external compressors lined up on one exterior wall would look quite ugly.)