The history of home cooling in the last two centuries starts with the invention of the fan. In 1886, Schulyer Wheeler invented the electric fan, which was the primary form of home cooling till after the second World War. The first air conditioner built for the home was created in 1914. Units were room air conditioners designed to sit on a window ledge. Frigidaire made the first room cooler to be available on the market for homes in 1929. They created year round Hot-Kold central air conditioner in 1931. Philco Air invented an air conditioner that used freon, that could be plugged into an electrical socket, and set in a window to cool homes in the late 1930's. New Smart Technology development will help further increase the efficiency of our home cooling systems. I hope these resources will give you the answers you are looking for, and please feel free to send another question if you need more specific info about this or any other subject!