open double hung window when window ac installed

[lordbaal]

I have a window AC. I want to open the window. It's a warm day, but not hot enough for the AC.

I do not want to remove it. With 3 herniated discs, I am not even trying to remove it.

If I do open the window, it will be held just by those accordion thing. I won't trust them with the weight.

I need something to go across the top part of the AC, when the window frame would slide into, on the top of the AC.

I tried looking online, I can't find anything.

The closest I came to finding something, is one of the top frame things on BBQ grills that you use when you build them to make it more rigid.

[Kato]

Two brackets, a piece of angle steel, and some time. Fasten a bracket to each end of a piece of angle steel, the steel being long enough to go across the width of the window. Fasten the angle brackets to the side on the window frame so that the angle steel holds the window unit in place instead of the window doing it. When you want the window open, open it and the angle steel will still hold the unit. When you want the window closed, you close it against the angle steel.

 

Why angle steel? Because it will act as a stop for any wind/rain/etc., that would go past the window when it's down. Add a piece of standard door insulation to the angle steel for a weather-tight seal.

[JimboS1ice]

Katos idea is ideal, you could also build a frame within the window and secure it that way but it won't look as clean as a bracket mount