Compared to a lot of other units, ductless air conditioners are quite simple in structure. It has an outdoor unit, indoor unit, refrigerant line-sets, power and control wires that connects them. The outdoor unit comprises the condensing coil, compressor, the expansion valve and a fan that helps in getting the airflow through the condenser coil. On the other hand, the indoor unit has the evaporator coil and a fan for the airflow. The line-sets that connects the indoor and the outdoor unit are made of insulated copper tubing that transfers the refrigerant.