Remove the drywall to reveal insulation and the edge of a stud.
How to put a window ac in a wall.
Secure the side panels with screws.
Measure the width of the wall opening and transfer that measurement to 2 2 x 4 s and cut them down to the matching length.
Window air conditioners often come with a foam insulating strip.
In the 3 8 c channel insert nut rod coupling on the end.
Put those four pieces of 2 x 4 lumber together to make a frame.
With the insulation removed mark the opening corners by drilling through the exterior sheeting with a long drill bit.
Drill hole on the side through channel and coupling than insert a screw.
Cut the strip of foam to the correct length and insert it between the upper window sash and the lower window sash.
Measure the height of the wall opening and subtract the combined thickness of the 2 x 4 s you just cut.
Extend the accordion panels from both sides of the air conditioner to the window sash track.
Also putting a new window unit in the wall voids its warranty and it will be less efficient i e more costly because you ll have to fill more gaps between the smaller machine and the wall.
Cut two pieces of the c channel in both sizes1 2 and 3 8.
Measure your a c from left to right including your frame.
Then cut those down to the matching lengths.
Before installing a window ac open the window as far as it goes remove the screen and clean the windowsill glass and window frame.
Use the level to ensure it is level and hammer it into place with nails into the opposing studs.
Do prepare the window and install brackets if necessary.