The basic function of an air conditioner is to pump in cold air. Cold air is pumped by forcing cold refrigerant which passes through coiled tubes. The tubes that are seen inside your home are called an evaporator and those placed outside is called a condenser. Hot air is pulled out and cooled making the room cold. It is inside the evaporator that the refrigerant starts evaporating pulling heat in the process thus cooling the air. The heat produced by the refrigerant is thrown outside through the condenser which is usual placed outside the house. Window air conditioners, split and central AC are a few types of cooling units. Among these the window type is more economical and easier to install but since they are fixed inside a room the cooling is confined only to that room where the unit is installed.
Opting for a central unit you can cool your entire house. The ducts attached to the unit helps to circulate cold air through out the house. This unit is subdivided into two types such as split and central systems. In a central unit the evaporator, condenser and compressor are packed together and are installed outside the house usually on the roof. The size of the unit varies according to the size of your house so you can’t install just any size or capacity in your house. To know the right size you will have to consult a professional HVAC contractor.