These are very similar to Single Split Systems but consist of one outdoor unit and several indoor units, this is extremely useful in situations where there is limited outdoor space to mount condenser units. Indoor units can be individually controlled to suit the environment in each room, all units are needed in the same mode i.e. heating or cooling. A Multi Split System system connects up to six indoor units to one outdoor, and also enables indoor units of different styles and capacities in one system. With this option there is also no need for duct work.