"Central air conditioning units are mainly of two types. They are the packaged units and the split-systems. In recent times, most homeowners prefer split systems to packaged units. There are some basic differences between the two units and each of them is suitable for a particular situation. For example, a house that has a furnace but not an air conditioning system, in such cases the best option is to install a split system.However, the basic difference between the two is that split systems mainly have three parts. They are the outdoor unit, the indoor unit, and the air handler unit. On the other hand, packaged units have all the components in a single cabinet and the cabinet in most cases is installed on a rooftop or on a concrete slab outside the building.Split systems have more energy efficiency than the packaged units. Some of the split systems have SEER rating as high as 25 while the highest SEER rating for packaged units is only 13. At the same time, the labor cost of installing a split system is more than that of a packaged unit. This is because two different units are being installed, one inside and the other outside.On the other hand, the packaged units have space efficiency as all the components are housed in a single cabinet and the installation cost is also lesser.Last but not the least, experienced opinion from HVAC experts need to be taken before installing an HVAC unit."