If your window slides from side to side, a slider/casement
air conditioner fits the bill for you. This air conditioner sits right on the open window space on the windowsill. The window to the side slides over and supports the air conditioner in place with a bar. Since slider window air conditioners vary in height, there is a filler panel that must be cut to fill in the space at the top to keep the outside elements out of the home. This is also a great solution for those who have a crank-out window. With crank-out windows, you will remove in the entire window pane. A piece of plexiglass is then cut to fill the space and a hole is then cut into the plexiglass for this air conditioner to be installed into.