Doors and Windows - weak windows & A/C units

Hi folks
I'm new here. Just wrote a long message and it timed out.
Here's a shorter version.
I live in Maine. It gets hot here for ~ 3 wks/summer. I decided I needed a window AC unit. Bought a 6000 BTU unit. Windows are 12 yr old, double pain (I mean pane), double hung. I don't know much about home improvement. Put the unit together, lifted it into the window frame, and realized that the lower sash, which you bolt the unit to, could easily just pop right out (It's on the 2nd floor, so that would be B-A-D)

I want to strengthen what the AC unit is screwed into, so I was thinking a strong slat of wood, bolted to window frame, on both sides on the inside, would work. I could then nail the window sash to this and mount the AC unit to the window sash, per instructions.

So - what kind of wood? What thickness? Is there some kind of bolt/screw that would work best?
Thanks for any input/advice!
Andrea

Yep...something like that would work.....you DON'T want to attach a window AC to a tilt type window.

Personally, I would consider taking a pc of 1x4 or 1x6 lumber long enough to catch past the frame and out onto the casing. I wouldn't bolt it to the window or the frame, but do bolt it to that upright flange on the top of the AC unit inside....then let the weight of the AC unit just hold it against the window casing....that way you don't mess up your windows.

You may have to use a spacer pc of wood to get the AC unit to sit back where it is supposed to....

By doing this, you could just leave that wood bolted to the AC and take the whole thing out for winter.......which you DO want to do, since it's about impossible to seal around a window AC for winter weather.

Thanks TnAndy!
That sounds like a great idea. By "spacer piece of wood" I assume you mean an additional piece of wood that would be added to the back of the 1x6, because the AC unit won't be flush w/ the window casing. How would I attach the spacer to the longer brace? Would long nails work (or might the weight of the AC unit pull them out, defeating the purpose)? Should I use wood screws long enough to go into both pieces?

Thanks again!
Andrea

YEah, you have the idea......and screws to attach the two together.....good excuse to buy that Makita cordless drill/driver, huh ? :)

The window will help support it some also just by the wood being against it, but the casing will do most of the support.

Or, you could just cut a hole in the WALL and mount the AC unit there, instead of in the window.

(Now there's an excuse to buy a Sawzall and a DeWalt cordless drill/driver!!)