Abstract: Arrangement and method for the prevention of water entering a pneumatic controller of a vacuum sewer system through a breather line. The proposed pneumatic controller is a non-bleeding controller preventing continuous flow of air from the breather line through the controller. The volume of breather air entering the controller during an evacuation cycle is smaller than the volume of a water trap provided in the breather line. The water trap removes water from the breather air before it enters the controller.

Abstract: A method and apparatus for evacuation of liquids, such as wastewater from e.g. wash basins, urinals, bath tubs or showers, whereby the liquid is collected in a sump, generates a hydrostatic pressure and is evacuated from the sump through a vacuum pipeline after a predetermined hydrostatic pressure is generated. In order to avoid flexible control conduits and to achieve time controlled evacuation with a simple mechanism, valves are integrated in a housing and operated by pressure differences acting on diaphragms after a certain hydrostatic pressure has been generated. One of the valves opens a connection between the sump and the vacuum pipeline to evacuate the liquid.