When these came out years ago, my parents put a big one in the window and it did pretty good. We use to call them "swamp coolers" because they do cause humidity. They are great in dry climates and will get pretty cool.

You may try a split. My DD uses those in her house and no window needed. Not sure exactly how they work but cools as good as central air.

Depending on the size, you may not have to mount it with screws. My smaller rooms have smaller units and they just sit in the window, it holds it in the frame. My larger one I have a stand that leans against the house to help support it. It depends on what you have. Most of the time I don't have more than one going and the other rooms can be closed off so the smaller units work great.

We have a Fujitsu that is 12"x 31" on room side, the motor/power is outside the room on the sidewalk; there is a small 3" hole in the wall where the air conditioner is hung high up on the wall. It will cool or heat up our 20x60' room in less than 20-30 minutes. It has been working for 8 years with no problem.

air conditioners
 

Could you tell me what brand and model you have? I bought a Hisense 400 sq ft portable air conditioner, but I am not sure if it works like I want it to. I am thinking of returning it, it only has 1 hose
Thanks
Jerseyrayne

Ours is a Haier unit. My husband thinks we got it either at Lowes or Walmart. My only complaint is that the control buttons eventually become hard to press.