A central air conditioner is either a split-system unit or a packaged unit.
In a split-system central air conditioner, an outdoor cabinet contains the outdoor heat exchanger, fan, and compressor, and an indoor cabinet contains the indoor heat exchanger and blower. In many split-system air conditioners, the indoor cabinet may contain the a furnace or the indoor heat exchanger of a heat pump. If your home already has a furnace but no air conditioner, a split-system may be the most economical central air conditioner to install.
In a packaged central air conditioner, the heat exchangers, compressor, fan, and blower are all located in one cabinet, which usually is placed on a roof or on a concrete slab next to the house’s foundation. This type of air conditioner also is used in small commercial buildings. The supply and return ducts come from indoors through the home’s exterior wall or roof to connect with the packaged air conditioner. Packaged air conditioners often include electric heating coils or a natural gas furnace. This combination of air conditioner and central heater eliminates the need for a separate furnace.
