Hydraulic system comprising a three-way valve, the three-way valve comprising a first port for the connection to a primary heat exchanger through the circulation pump, a second port and a third port for connection to the heating circuit and to a secondary heat exchanger, respectively. The three-way valve is switchable between two positions in which the first port is in fluid communication with the second port or with the third port. The three-way valve is responsive to the pressure applied by a circulation pump, and has a displaceable obstructing member that may be moved due to transitions between an off-state and an on-state of the circulation pump. The obstructing member comprises a pair of sealing surfaces facing away from each other and suitable to engage reciprocatingly respective opposed seats of the three-way valve.

Heat transfer systems employing a heat transfer means (e.g., circulating fluid, thermally conductive material, etc.) to transfer heat from the heat source (e.g., fireplace, wood stove or other heat source) to a remote location of a home, residence, building or other structure.

A water heater includes a heat exchanger. A controllable three-way proportional valve provides a proportionally controllable flow to the hot water inlet of the heat exchanger and a boiler return water outlet. A mixing tank mixes a cold water and a hot water. The mixing tank provides a time delayed mixed water. A temperature sensor is disposed in or on the mixing tank to measure a temperature of the time delayed mixed water to provide a time delayed mixed water temperature. A feedforward control process running on a processor adjusts a proportional operating position of the controllable three-way proportional valve to regulate a temperature of hot water at the hx domestic hot water outlet based on the temperature of the time delayed mixed water temperature. A method for controlling a hot water temperature of a water heater a water heater using a flowmeter based feedforward control are also described.

The objective of the present invention is to provide a boiler system for bath heating and hot water that is capable of performing heating and hot water preheating by using a single circulation pump for both without the need to separately include a circulation pump for heating and a circulation pump for hot water preheating. In order to achieve the above objective, the present invention provides a boiler system for both heating and hot water, comprising: a heat exchanging unit; a heating water channel connected between the heat exchanging unit and a place to be heated; a tap water supply pipe for supplying tap water to the heat exchanging unit; a hot water supply pipe for supplying hot water to a place requiring hot water from the heat exchanging unit; a hot water recirculation channel connected to the hot water supply pipe at a first branch point branched from one side of the heating water channel; a hot water bypass channel connected from the second branch point branched from the other side of the heating water channel to the tap water supply pipe; and a circulation pump disposed between the first branch point and the second branch point.

A mixing device includes a first inlet (84) and a second inlet (86) inlet and an outlet (80). The first inlet (84) is connected to the outlet (80) via a first flow connection and the second inlet (86) is connected to the outlet (80) via a second flow connection. A circulation pump assembly (24; 46) includes an electric drive motor (30), a control device (34), for controlling the speed of the drive motor (30), and at least one impeller (68; 100) driven by the drive motor. The at least one impeller (68; 100) is positioned in the first flow connection. The flow connections are configured such that at least one hydraulic pressure generated by the impeller (68; 100) in the first flow connection acts as hydraulic resistance in the second flow connection.

A hot water supply system according to the present invention includes: a hot water supply unit configured to supply hot water; an opening and closing valve configured to connect a hot water supply pipe, which is configured to supply hot water to a user from the hot water supply unit, and a cold water supply pipe, which is configured to supply cold water introduced from a cold water inflow pipe to the user, to allow water to flow or configured to disconnect the hot water supply pipe from the cold water supply pipe to block the water from flowing; a circulation pump configured to circulate water supplied from the hot water supply unit through the hot water supply pipe, the opening and closing valve, the cold water supply pipe, and the hot water supply unit; and a control unit configured to, when a water-preheating signal of the user is input, open the opening and closing valve, and operate the circulation pump to preheat water which is to be supplied to the user.

Heat transfer systems employing a heat transfer means (e.g., circulating fluid, thermally conductive material, etc.) to transfer heat from the heat source (e.g., fireplace, wood stove or other heat source) to a remote location of a home, residence, building or other structure.

A hot water supply system decouples an intelligent hot water storage system from a water heating engine system. The water heating engine system includes a plurality of instantaneous water heaters that provide for redundant operation for improved reliability. The intelligent hot water storage system includes a storage tank that encloses a volume for storage of water. The intelligent hot water storage system includes a recirculation loop driven by an integrated pump and operated by an integrated controller. By positioning the tank recirculation outlet and inlet farther apart from each other, additional usable volume of hot water is provided by the intelligent hot water storage system. Isolation valves positioned on the input and output of a recirculation pump in the recirculation loop facilitate repair or replacement of the recirculation pump. The hot water system provides for increased capacity while providing redundant heating engines in a smaller floor space than conventional systems.

A centrifugal pump assembly includes an electrical drive motor (4, 6), an impeller (14) which is driven by the electrical drive motor (4, 6) as well as with at least one valve element (18) which is directly or indirectly movable along a first movement path between at least two switching positions, by the electrical drive motor (4, 6). At least a part of the valve element (18) is additionally movable along a second movement path which is different to the first movement path, between a released position, in which the valve element is distanced to at least one contact surface and a bearing position, in which the valve element bears on the at least one contact surface.

A pump assembly includes an electrical drive motor, at least one impeller (14) which is rotatingly driven by the electrical drive motor as well as a control device (17) which activates the drive motor. The control device (17) is configured such that the control device (17) selectively activates the drive motor in at least one first or a second operating mode. In a first operating mode, the drive motor is activated by the control device (17) such that a rotor (6) of the drive motor continuously rotates. In the second operating mode the drive motor is controlled by the control device (17) such that the rotor (6) of the drive motor is moved further stepwise manner in at least one selected angular step of preferably smaller than 360.