An outdoor unit connects an indoor unit in a 1-to-1 configuration.
It is suited to where there is sufficient space for an outdoor unit,
or for additional air conditioning system.
An outdoor unit connects to more than 2 indoor units operating
in more than 2 rooms. It is best suited to houses with
a number of floors and rooms with little space for an outdoor unit.
A window unit is stored inside a window frame. They can be
installed with a simple method even if there’s no space on the wall.