Side back to back installations
Indoor unit located in the corner of the room
In a lot of apartment buildings there is not enough room to mount the indoor unit on the external wall for a variety of reasons. In this case there is not enough space between the window and the roof.
The simplest solution is to mount the unit on one of the adjoining internal walls. To do this the right or left side of the unit (depending on what side of the room it is going on) touches the external wall.