An apparatus includes a pressure housing configured to be coupled to a vacuum source and a diaphragm sealingly coupled to the pressure housing. The diaphragm is configured to move in response to the vacuum source. A magnet is coupled to the diaphragm. A magnetic switch is disposed opposite the magnet and is configured to be actuated by the magnet when the magnet is a predetermined distance from the magnetic switch. The magnetic switch is configured to selectively actuate the vacuum source.
