Disconnect
Because HVAC systems rely on high voltage, building codes require air handlers and condensers to be connected to disconnect switches to allow technicians to cut power from the electrical source separate from thermostats or off/on switches. Code requires that disconnects be located within sight of the HVAC unit to ensure that power will not be accidently restored while a technician is working on the equipment. As a safety switch, disconnects are typically the same as breakers found in electrical panels, but separate and directly tied to the HVAC system.