Window air conditioners can be plugged into a regular 120-volt outlet, but they can also be hardwired into your home’s electrical system. Hardwiring is usually done by an electrician, and it involves connecting the AC unit to a dedicated circuit. This ensures that the window AC doesn’t overload your home’s electrical system and trip the breaker. It also gives you the option to install a switch so you can turn the unit on and off without having to reach behind it and plug or unplug it.