Abstract: A pump system for liquid media includes at least one pump having a suction side and a delivery side, a control unit connected to the at least one pump, and at least two controllable valves connected on one side thereof to the suction side. The valves are controlled by the control unit connected thereto, such that each valve only allows passage of medium from a first source or second source connectable to their respective other valve sides. The pump system also includes at least one level sensor connected to the control unit, which level sensor is positioned at least near the source where, in the case of a critical level being exceeded, medium must be pumped away.

Abstract: A pump system for liquid media includes at least one pump having a suction side and a delivery side, a control unit connected to the at least one pump, and at least two controllable valves connected on one side thereof to the suction side. The valves are controlled by the control unit connected thereto, such that each valve only allows passage of medium from a first source or second source connectable to their respective other valve sides. The pump system also includes at least one level sensor connected to the control unit, which level sensor is positioned at least near the source where, in the case of a critical level being exceeded, medium must be pumped away.

Abstract: A system including a not self-priming medium pump including a pump head for supply of medium, a valve coupled to the pump head and which includes a passage operated by a float, and an air pump connected to the valve. The system controls the level of the medium in the pump head by the float. The float is shaped such that, when the pump head is filled with medium, an increasing upward force of the float is sufficient to close the passage in time. By virtue of optimized timing of, in particular, the closing, but also the opening, of the passage, both efficiency of the medium pump and service life of the air pump are improved, while the system is self-priming.