Controller for vacuum sewage system

A controller for a vacuum sewage system, the system including a holding tank at substantially atmospheric pressure, a valve pit, a sensor pipe having a first end extending into the holding tank and a second end extending into the valve pit, a valve located in the valve pit, a discharge conduit for conveying sewage from the holding tank to a location exterior to the holding tank, the discharge conduit having a first section and a second section, the first section having a first end located in the holding tank and a second end in fluid communication with the valve, the second section having an end in fluid communication with the valve and a vacuum source for maintaining the second section of the discharge conduit under vacuum, the controller including:

• a housing having an outer surface defining a housing interior;
• a first chamber located in the housing;
• a pressure sensor conduit having a first end in pressure communication with the sensor pipe and a second end in pressure communication with the first chamber;
• a second chamber located in the housing;
• a first port in communication with the second chamber and with a source of atmospheric pressure;
• a first flexible diaphragm located between the first and second chambers;
• a third chamber located in the housing;
• a second port extending between the second chamber and the third chamber;
• a first valve member located at least partially within the second chamber for selectively opening and closing the second port so as to selectively permit or prevent air flow between the second and third chambers through the second port;
• a third port in communication with the third chamber;
• a fourth chamber located in the housing;
• a second flexible diaphragm located between the third and fourth chambers;
• a first air flow path between the third and the fourth chambers, the first air flow path located on one side of the controller completely within interior of the housing;
• a fifth chamber located in the housing;
• a fourth port in communication with the fifth chamber and with the second section of the discharge conduit;
• a second air flow path between the third, fourth and fifth chambers, the second air flow path located on the same side of the controller as the first air flow path and located completely within the interior of the housing;
• a second valve member located at least partially in the second air flow path to selectively permit or prevent air flow between the third, fourth and fifth chambers;
• a sixth chamber located in the housing;
• a fifth port in communication with the fifth chamber and the sixth chamber;
• a sixth port in communication with the sixth chamber and with a source of substantially atmospheric pressure;
• a third valve member located at least partially in the sixth chamber for selectively opening and closing the fifth port so as to selectively permit or prevent air flow between the fifth and sixth chambers through the fifth port and for selectively opening and closing the sixth port so as to selectively permit or prevent air flow between the sixth chamber and the source of substantially atmospheric pressure through the sixth port;
• a seventh port in communication with the sixth chamber;
• a third air flow path between the second chamber and the seventh port, the third air flow path located completely within the interior of the housing on a side of the controller opposite the first and second air flow paths;
• and
• a fourth valve member located at least partially in in the third air flow path.