These systems are by far the most common type of central air conditioning system currently being used. They consist of the condenser and compressor placed outside in a metal cabinet in one package. A separate evaporator is placed indoors within a segregated container, usually located in a closet or the attic. The outdoor unit provides the refrigerant to the evaporator, which then cools the air and pumps it down the network of central air ducts through an air handling unit.
Split central air conditioners are usually three times the size of an equivalent packaged central air conditioner. Splitting them in two makes the size much more manageable.
On the other hand, in a packaged central air conditioner, all the components, including the condenser, compressor, and evaporator, are in one single unit. You can either have these installed on a concrete slab next to your house or the roof.
This system is best suited for commercial buildings, or already built homes, where space can often be limited indoors. Central air ducts then circulate the air from the air handling unit into the room and move it back to the unit. These systems can be coupled with heating coils or furnaces to provide heating facilities too.
Packaged central air conditioning systems generally provide lower efficiencies than split systems but have the advantage of not taking up any space inside your home.