Window AC / August 26, 2018 / Denise Brisette
The back the part that hangs outside should have the vents where water will drip out. Carefully place it on the window sill facing the right way. There should be ridges around the perimeter of the air conditioner to show you where it should line up with the window. Once you have this lined up slide open the side panels. These are designed to fill up the rest of the window that the device does not fill. Slide them as tightly over as you can. Have the top sash of the window lowered carefully and slowly down until it comes into firm contact with the top of the conditioner. The frame should be very tight against it to brace it and keep it from falling.
The answer is It depends on the wall thickness. Sleeve specifications for some window air conditioner manufacturers include the maximum wall thickness before it will cover part of the louvers. For example Amanas 18000 BTU models have a max of 8.5 inches. If the wall thickness is at or below that these models can be used in as a wall air conditioner without adversely affecting function. So whats the problem if the wall covers a little of the louvers? Two things: 1) restriction of air movement and therefore reduced efficiency and 2) these units pull air in very powerfully. Cut wall edges could become loose allowing material to be sucked into the unit and potentially causing damage.
The most commonly used air conditioners are window air conditioners. This is due mostly to the fact that they are the cheapest alternative when it comes to cooling our homes. But there are other reasons also. For example they install in a window out of the way. Install it and forget it. These units are also available with electric heat options. Window air conditioners were once so noisy that they were nicknamed window bangers. This term was very accurate and well deserved. However todays window air conditioners are very different from the ones many of us learned to hate.