The Emerald design increases cooling and heating capacities while reducing amperage. The molded composite no-rust drain pan is shaped to provide positive drainage even when the boat heaves and rolls. Emerald condensers can be installed quickly and easily. The drain, seawater and refrigerant connections are conveniently located to conquer installation challenges thus reducing installation time by up to fifteen minutes. The electrical box can be easily removed and located up to 5 ft. (1.5 m) away, further reducing the size of the unit while making the system more accessible. The reversing valve, pressure switches and service ports are centrally located, high on the unit for access from any side.