The majority of AC ceiling fans have a summer/winter switch located on the motor itself, or a reversing button on the remote control for DC ceiling fans. When you have your fan in summer mode the fan rotates anticlockwise to provide a cooling breeze beneath the fan and circulate air around the room. Conversely, having the fan on winter mode the fan rotates clockwise to bring the warm air down the walls from the ceiling without producing a strong draft beneath the fan to help circulate warm air around the room.