Self-contained units are typically the best choice for smaller boats, up to about 40 feet (12m), due to the lower cost of the units and installation.
A self-contained air conditioner has all of the major components mounted on a single chassis which is installed in the living area; usually under a bunk or settee, or in a locker. Cooling-only models and reverse-cycle heat pump units are available.
A single unit can cool one cabin, or it can be ducted to two or more cabins to save space and cost.
Self-contained units often require less power than other systems due to the highly efficient rotary compressors.