Apparatuses, systems, and methods for de-energizing an indoor HVAC unit are provided herein. The system comprises an outdoor HVAC unit, an indoor HVAC unit, signal cables coupled between the outdoor HVAC unit and the indoor HVAC unit, and an air-gap switch connected to the indoor HVAC unit. The signal cables are configured to electrically power the indoor HVAC unit from the outdoor HVAC unit. The air-gap switch is connected to the indoor HVAC unit and is configured to selectively sever a connection between the signal cables and the indoor HVAC unit. The air-gap switch provides an electrical safety measure for servicing and maintaining the indoor HVAC unit.