I had an idiot I worked for who owns a bunch of bldgs in Pittsburgh. Wanted me to install a 7.5 ton package unit A/C only on the 12th floor of one of his buildings. I thought he wanted me to hang it out the window. It got better. I was to set it on the floor and duct the condenser air in and out of this window. Right next to offices, i'm sure the noise wouldn't have bothered anyone. Let's just say it got hauled out and we went a different route.