What model of an air conditioner is installed in your office? Do you have a remote control option? Perhaps someone is sending the air conditioner the wrong commands, and it's turning off. I say this because even the repair company says nothing wrong with the air conditioner. I'd also check if everything is okay with the condenser or the main connection. We had this happen to our home air conditioner. We fixed it so many times and ended up buying a new one at brightcamping.com. Now our air conditioner doesn't bother us anymore.