One of the best ways to maintain and increase the efficiency of an AC unit is to clean the unit regularly to prevent any damages or clogs caused by the debris. It also is important to make sure that the air conditioner unit is not running constantly. If possible, drawing blinds and curtains can help cool down a room on hotter days. Making sure that all the windows and doors are sealed will also help increase the efficiency of the AC unit as it will help contain all the cool air in the room.