Central Air Conditioners Central air conditioners are designed to cool the entire house. Most are known as "split systems," meaning the air conditioner's main components are separate from each other. The cooling coil evaporator is mounted inside the home, usually in the furnace plenum; while the other major components (the compressor and condenser coil and fan) are located outdoors. Split systems use the same ductwork used by the forced warm-air furnace. Heat pumps are like central air conditioners, except that the cycle can be reversed and used for heating during the winter months

The system has an outside condensing unit, very similar to a regular split system air conditioner. It also has copper tubing running to an indoor unit. However, the indoor unit(s) (It can have multiple indoor units with one outdoor unit) are not ducted, they simply hang on a wall or mount in the ceiling. These are not put in a window – like the window air conditioner, and they don’t need a huge hole in the wall. They are much quieter than window units, because the noisiest part of the system is outside. Another advantage is the ability to have multiple indoor “blower” units, giving you air conditioning in more than one room.