What is Central Air Conditioning? Central Air Explained

The typical residential central air conditioning system has an evaporator coil in the main duct of a forced air furnace

Photo Courtesy of Ben Cooper via Flickr

The typical residential central air conditioning system has an evaporator coil in the main duct of a forced air furnace. The furnace blows hot air throughout the home in the winter. The same blower is used to force air over the cold evaporator coils of the air conditioning system to cool the air and extract humidity in the summer.

Parts and Function of the Central AC System

The evaporator coil of the central AC unit is inside the home. These coils are cold, and warm household air flows over them to get cooled. Outside the home is the rest of the air conditioning system. It is a metal or plastic housing with a large fan and the condenser coil along with the compressor. The compressor pumps refrigerant through pipes that are sized to cycle the refrigerant back and forth between a liquid state and a gaseous state as it is passed through small and large fittings under pressure from the compressor. A copper pipe makes a circuit from the outside part of the central air unit to the inside evaporator coil and back. Refrigerant at the evaporator coil is cold. It absorbs heat in the air blowing over it, taking it outside to be dissipated by the condenser coil and fan before traveling back into the house.

Other AC Systems

Window units combine both coils into one housing that fits a window. The hot condenser coils are on the back and the cold evaporator coils are on the front. For homes without a forced air heating system that do not want window units, there are component units that connect the inside and outside parts through the wall. Inside the evaporator and blower, housing is attached to a wall with a small hole for pipes running outside to the condenser, fan and compressor.

There is a solution to fit any home with an AC unit that will keep the home cool during the hottest summers. Central air is the easiest and best answer because it can equally distribute cool air to each room that has a duct running to it.