Disadvantages. The primary disadvantage of mini-splits is their cost. Such systems cost about $1,500 to $2,000 per ton (12,000 Btu per hour) of cooling capacity. This is about 30% more than central systems (not including ductwork) and may cost twice as much as window units of similar capacity.

Place the AC on the wall so that it won't obstruct airflow. This will guarantee that the system operates efficiently and evenly cools the entire bedroom. Install a split AC at least 7 feet above the floor on either side of your bed. The best place to install a split AC is the central location of your bedroom.

Here's where the systems differ: central air systems include one indoor unit for the entire home; mini split systems require an indoor unit in every separate room that needs conditioned air. These indoor units are available as wall mounted, under ceiling, floor mounted and in ceiling.