The present invention improves the user-friendliness of a hot-water supply apparatus when using hot water supply and air conditioning. A switching control unit 27, which switches between heat medium flow paths 4 and 5 according to an air conditioning ready state or a hot-water supply ready state, switches a heat medium flow path to the hot-water supply ready state by a switching valve 21 in the case where air conditioning is not used by the time an air conditioning standby time elapses during standby in the air conditioning ready state.

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.

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.

Provided is an air pressure regulating device comprising an expansion tank having air stored therein and having an air injection/discharge port at an outside thereof; and a pressure regulation unit provided with a three-way ball valve connected to the air injection/discharge port, a pressure gauge which is installed in any one of flow paths of the three-way ball valve to check an internal pressure of the expansion tank, and a valve core which is installed in a flow path other than the flow path in which the pressure gauge is installed to be capable of injecting or discharging air into or from the expansion tank so as to be capable of controlling the internal pressure of the expansion tank.

An electric water heater is disposed close to a faucet to readily provide heated water to the faucet. This heater provides heated water without the wait required to obtain hot water from the main, remotely-located, hot water heater such as a hot water tank. The electric hot water heater includes a heater tube disposed in contact with an electric resistance heater. The electric resistance heater does not directly contact the water in the heater tube. The electric resistance heater heats the sidewall of the heater tube which, in turn, heats the water in the heater tube. Two layers of insulation are disposed over the electric resistance heater. The heater tube is placed in line with the regular hot water supply pipe.

A latent heat storage system includes at least one latent heat storage device which contains a storage medium with latent heat, at least one heat pump coupled to the latent heat storage device, at least one extraction circuit which has a first heat carrier medium and with which, during normal operation, in accordance with the intended purpose, heat can be extracted from the storage medium and supplied to the heat pump on the input side, and an extraction heat exchanger which is in contact with the storage medium, wherein the extraction heat exchanger is connected to the extraction circuit. Between the extraction heat exchanger and the heat pump, a coupling device is arranged in a connection line, which at least temporarily supplies a second heat carrier medium, which can be heated by at least one heat source, into a section of the connection line. A method for operating a latent heat storage system is also provided.

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 hydraulic construction unit for a heating facility or air-conditioning facility, includes a return connection (20) and a first feed connection (16) for a heating circuit (6), with a heat source outlet (12) fluid conducting connected to the return connection. A heat source inlet (14) is fluid conducting connected to the first feed connection and to a circulation pump assembly (28) in a flow path between the return connection and the heat source outlet (12) or in a flow path between the heat source inlet and the first feed connection. A second feed connection (18) for a second heating circuit (8), is fluid conducting connected to the heat source inlet and to the return connection. A mixing valve (54) is arranged in a flow path from the heat source inlet to the second feed connection and/or in a flow path from the return connection to the second feed connection.

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.

A system produces domestic hot water and includes a tank having top and bottom portions and containing heat storing fluid, and a tapping unit including first and second tapping coils. The first tapping coil is immersed in the bottom portion of the tank. The second tapping coil is fluidly connected in series to the first tapping coil by a connection pipe, and to the hot water port, and is immersed the top portion of the tank A switching device switches between a first state in which water flows from the cold water port through only first tapping coil to the hot water port, and a second state in which water flows from the cold water port through the first tapping coil and, after flowing through the first tapping coil, through to the second tapping coil to the hot water port.