The main 3 types of systems are self-contained units, split systems, and chilled water systems. Self-contained units units are compact, convenient systems fueled by refrigerant and typically are used for 1-2 rooms. Split systems are the most similar to home A/C - used to cool multiple rooms, major components are split between two units connected by insulated copper tubing. Lastly, the chilled water system is used for large boats and utilizes freshwater that is pumped around a piping loop to cool or warm the cabin.