Ductless mini splits have three major components: the compressor, which is installed outdoors; the air handlers, which are installed indoors; and the remote control. The indoor components are connected to the outdoor unit through a hole in the wall about three inches in diameter. In general, mini splits are simple systems, but they must be installed correctly for them to function properly. Installation kits are often available for those who want to do their own installation, but in most cases, it’s a better idea to let a professional install the equipment. Minisplitwarehouse.com