proper a/c size for 2014 SO 439 2 cabin

[westmich]

Can anyone offer an opinion on the correct a/c unit(s) and BTU size for a two cabin SO439?  Last boat (36') had single compressor 15,000 BTU unit was OK but had trouble keeping all areas cool when temp got close to 90 degrees.  I don't want to under power A/C on this boat.

Single 18,000 unit seems to be one option or two compressor setup with lessor BTU's is other option (although $5k more).

[rxc]

I have a two-cabin SO43DS, with a 16K unit in the middle to heat/cool the salon and the fwd cabin, plus an 8K unit to handle the aft cabin. They work well, and can keep everything at the proper temperature. Webasto units.

[Tafika II]

We have 5K BTU unit for the after cabin and a 7K for the main salon in forward cabinMarine Air L-2314.pdf (376.17 KB). Main servicing is the water intake filter and the air vent cleaning. Has worked flawlessly for coming up on 7 years.

[Deleted]

We have a 45DS with three Cruise Air units - 2 - 8 BTU compressors for forward and aft cabins and a 16 BTU unit for the main salon. They work great in south Florida where we are dealing with a minimum of 4 months of 90+ degree temperatures.