A pump assembly is disclosed comprising a pump body having a first pump stage housed in the pump body including a fluid inlet and a first and a second fluid outlet. A flow feed chamber is housed in the pump body in fluid communication with the second fluid outlet. A second pump stage housed in the pump body is in fluid communication with the flow feed chamber and includes at least one fluid outlet connected to the second pump stage. A valve assembly is operable into a first position to fluidically connect the fluid inlet through the first pump stage to the first fluid outlet. The valve assembly is further operable into a second position to fluidically connect the first pump stage to the second fluid outlet and the flow feed chamber and the flow feed chamber fluidically connected to the at least one fluid outlet through the second pump stage.

An air conditioning system (1) has a heater unit (3) providing a hot water flow (7) and receiving a hot water return (31) in hot water loop, a chiller unit (5) providing a cold water flow (13) and receiving a cold water return (33) in a cold water loop, one or more air to water heat exchangers (17), and one or more control valves (11), each control valve (11) associated with one of the air to water heat exchangers (17) and arranged to receive the hot water flow (7) and cold water flow (13), selectively provide the flow from a one of the hot water loop or cold water loop to the associated air to water heat exchanger (17), receive a return from the associated air to water heat exchanger (17), and selectively provide the return from the associated air to water heat exchanger (17) to the return of the one of the hot water loop or cold water loop.

A circulation pump assembly for a heating and/or cooling system includes an electric drive motor (108) and a connected pump housing (106) in which at least one impeller (118) is situated and which comprises a first inlet (112) and a first outlet (114). The pump housing (106) includes a second inlet (122) which is connected in an inside of the pump housing (106) at a mixing point (130) to the first inlet (112). A regulating valve (134), which is designed for regulating the mixing ratio of two flows mixing at the mixing point (130), as well as a control device, which controls the regulating valve (134) for regulating the mixing ration, are arranged in the pump housing (106). A hydraulic manifold is provided with such a circulation pump assembly.

Three-way valve drivable by a pump, switchable between at least two switch positions wherein a first port is selectively in fluid communication with a second port or with a third port. The three-way valve comprises a movable support and a pair of obstructing members carried by the movable support, at least one of which is responsive to the pressure applied by the pump at the first port, at least one of the movable support and obstructing members being movable due to transitions between an off-state and an on-state of the circulation pump. The obstructing members are adapted to engage reciprocatingly the respective seats of the three-way valve. The obstructing members are capable of changing shape synchronously when the pump switches from the off-state to the on-state.

A pump assembly includes an electric drive motor (4, 6), an impeller, driven by the drive motor (4, 6), and a valve device (18) situated in a flow path through the pump assembly, which is movable between a first and a second switching position. The valve device (18) is coupled to the drive motor via a first coupling such that a movement of the drive motor (4, 6) is transmitted onto the valve device (18) and the valve device is movable from the first into the second switching position by rotation movement of the drive motor. The first coupling is releasable by way of increasing the speed of the drive motor (4, 6) and/or increasing the pressure at the outlet side of the impeller and/or by way of slip, such that the coupling between the drive motor (4, 6) and the valve device (18) is reduced or lifted.

A pump assembly is disclosed comprising a pump body having a first pump stage housed in the pump body including a fluid inlet and a first and a second fluid outlet. A flow feed chamber is housed in the pump body in fluid communication with the second fluid outlet. A second pump stage housed in the pump body is in fluid communication with the flow feed chamber and includes at least one fluid outlet connected to the second pump stage. A valve assembly is operable into a first position to fluidically connect the fluid inlet through the first pump stage to the first fluid outlet. The valve assembly is further operable into a second position to fluidically connect the first pump stage to the second fluid outlet and the flow feed chamber and the flow feed chamber fluidically connected to the at least one fluid outlet through the second pump stage.

A method controls a circulation pump (1) in an installation with at least two circulation circuits (3, 4), with which the circulation pump (1) is integrated by way of a switch-over valve (2) into the one or the other circulation circuit (3 or 4) depending on the switched position. The pump (1) is activated differently depending on the switched position of the switch-over valve (2). The switch-over procedure is detected by way of determining the pressure course and/or the flow rate course in the pump (1) or an electrical variable which is dependent thereon, of the motor driving the pump, and the pump (1) is operated in another manner accordingly.

A centrifugal pump assembly includes an electric drive motor (6, 8), a driven impeller (14) and a pump casing (2) which surrounds the impeller (14). A movable element (24; 24) is arranged a valve element. A section of the valve element is movable from a released position into a bearing position, fixed on a contact surface (60), by pressure which is produced by the impeller in the pump casing. A control device (64) moves the valve element from one switching position into another switching position and reduces the speed of the drive motor. Upon pressure in the pump casing dropping such that the valve element is no longer fixed on the contact surface and the valve element has been moved into the other switching position, the control device increases the speed of the drive motor again. A method for moving a valve element is provided.

A hydraulic system includes at least one pump assembly and a switching device which includes at least two switch positions. The switching device is configured such that on operation of the pump assembly in a first operating condition, the switching device is held in a stable manner in each of the at least two switch positions in each case by the hydraulic forces in the system. In a second operating condition of the pump assembly, the switching device is moved from a first switch position into a second switch position, assisted by switching energy stored in the first operating condition. The hydraulic system is configured such that in the first operating condition, the switching energy is stored independently of a switching-over of the switching device between the switch positions. A method is provided for operating such a hydraulic system.

A pump assembly includes an impeller (18), which for rotation is connected to an electrical drive motor (20) which can be driven in two rotation directions (A, B) and a valve (10) situated in an inlet of the pump assembly. The valve includes a valve element (48) movable between at least two switch positions and is connected for movement to a drive element (36, 60) subjected to the flow produced by the impeller (18). The valve element (48), in at least a first of the two switch positions, closes an inlet channel (44, 46) of the pump assembly (12) and is arranged such that the movement direction into this first switch position corresponds to the flow direction (S1, S2) through this inlet channel (44, 46). A hydraulic system is provided with two circuits and such a pump assembly. The valve serves as a switch-over valve between the two circuits.