Wall Mounted Units
A split air conditioning system puts the compressor and
condenser outside the building and the evaporator and fans inside the building.
In a central air conditioning system, fans push cooled air from a centrally
located evaporator through ducts to the entire building. In a ductless split
system, fans in a wall-mounted unit move the air from the evaporator into the
room in much the same way that a window unit does. Because the split unit's
noisy compressor is outside, however, a split ductless system is much quieter
than a window unit.
Split units are efficient, but because they require the
installation of equipment outside the building, they might not be suitable for
high-density residential areas, such as apartments in urban areas.