Suggestions for supporting Window AC

[Gibbelstein]

We bought a window AC for the bedroom (the idea being that we can be sufficiently cool during the day elsewhere in the house or out in the world), but I have never installed one before.  They seem designed to be kept in place completely by the lower sash, but that doesn't seem particularly sturdy to me.  I bought a bracket to hold it (similar to this https://www.amazon.com/AC-Safe-AC-080-Light-Duty-Conditioner/dp/B002YFWDXQ/ref=sr_1_1?ie=UTF8&qid=1469209116&sr=8-1&keywords=window+ac+bracket ) but there is a roof section that comes within a couple of inches of the window, so this will not work. 

• Am I being paranoid about the ac putting too much pressure on the lower sash? (Does it matter that the house is almost 80 years old, and I am unsure of the condition of the windows other than "looks OK, but could use some paint"?
• Does anyone know of a bracket that supports it from above, or some other way?
• I considered using the bracket I bought, but with a board going straight down, supporting the AC from the lower roof area like a kickstand.  This is not a good idea for the roof area, even with padding on the bottom of the board, right?

If it is a factor in your input, here is the AC in question: https://www.amazon.com/LG-LW8015ER-Window-Mounted-Conditioner-Control/dp/B00V3IYN06/ref=sr_1_1?ie=UTF8&qid=1466562289&sr=8-1&keywords=LG+LW8015ER

Thanks for any suggestions!
Chris

[rugorak]

Honestly depends on the window. In general I think you'd be fine. In fact usually old windows are so heavy it will be held in place better than a newer window. And if your jambs are in question well you should be worried about the windows anyway.

Probably your bigger worry is if the windows are old do they have a good weep holes. If not you could get water damage.

[Gibbelstein]

Honestly depends on the window. In general I think you'd be fine. In fact usually old windows are so heavy it will be held in place better than a newer window. And if your jambs are in question well you should be worried about the windows anyway.

Probably your bigger worry is if the windows are old do they have a good weep holes. If not you could get water damage.

Ha, I had thought of that also.  And now that I'm thinking of it, the whole ~60lb is not resting against the sash.  I guess it is also a bit unnerving that so much of it sticks out the window, and it is not balanced with the weight resting on the sill in the middle of the unit.

[BudgetSlasher]

There is a company called AC-safe that makes a few styles and strengths of supports (you can find them on home depot or amazon).

I used one in my last house on a second story window, not so much for support one the AC was in, but to be able to set the AC in place and then close the window. Makes it easier to install and remove by yourself. Now that I have more DIY experience, work space and tools I would probably whip something just as functional out of some PT or cedar.

I agree with what has been said, if your window cannot handle a window AC you have bigger issues than what bracket to use as a support.

[bobechs]

1. Stack of concrete blocks

or,

2. 2x4 balanced on a stack of concrete blocks

[Gibbelstein]

Thanks for the suggestions, Slasher.  I did look into AC safe and other companies, but when I reread the instructions for the AC, I see that they provided little brackets that will help a bit. 

And Bob, I don't think I would place concrete blocks on the roofing, but you did bring up something I hadn't thought of, which is that if I do have to put any supports down to the roofing itself, I will need to spread it out over a larger area.  So, if I need to do it, I would use something like a patch of plywood to distribute the weight a bit better.  Thanks!

[Tjat]

I don't think you have to worry. I had window ACs growing up and never had an issue with instability, even without any bracket underneath. However, as an added precaution, you could cut a length of 2x4 to fit between the top of the window (inside the house) and the movable bottom half of the window. This would put added pressure to keep the window shut tight against the top of the AC. I hope I explained that clearly