The present disclosure provides a water heating system for efficient heating of water for immediate use that fits either to industrial applications or household applications. The water heating system is suitable to be combined with a solar heating unit and it can be operated on electric power or on gas-based heating units for providing hot water to multiple consumers for household or industrial utilization. Furthermore, the system can be stand-alone, operating without any additional water heating system and can provide an immediate stream of hot water, e.g. it can be installed within a water supplying appliance. The water can operate in two modes: (1) heating for immediate use of hot water; and (2) heating water to be contained in a reservoir for later use. The system uses a two (bi) directional flow valve.

A method of heating water in a water storage tank. The method includes: selecting an outlet port and an inlet port from at least three ports located in the tank at different heights along a vertical direction. The outlet port is below the inlet port. The method further includes extracting water from the outlet port, supplying the extracted water to an external heat exchanger configured for heating the extracted water, and delivering heated water from the heat exchanger to the selected inlet port.

Embodiments of the invention provide a pool heater including a housing, a first tankless heater, a second tankless heater, and a controller. The controller is configured to activate only the first tankless heater when a first condition is met, activate only the second tankless heater when a second condition is met, and activate the first and the second tankless heaters simultaneously when a third condition is met.

A heat pump may include a compressor configured to compress a refrigerant, a first temperature sensor configured to detect an outdoor temperature, a second temperature sensor provided in heating pipes connected to a heating device, and a controller. Based on a first sensing value of the first temperature sensor, the controller may be configured to control a compressor, control power to a boiler, and/or calculate an expected efficiency of the heat pump. Based on the expected efficiency and/or a second sensing value of a second temperature sensor, the controller may be configured to control power to the boiler.

Dispensing of hot water having an adjustable temperature by way of a water outlet fitting that can be installed on a sink. This is achieved by a continuous flow heater and a measured value sensor arranged in a water inlet of the water outlet fitting as the hot water heater. The measured value sensor detects a measurement variable with regard to water flowing through the continuous flow heater (10). The water dispensing device has a control unit, which is designed to regulate a flow rate through the continuous flow heater as a function of measured values of the measured value sensor in order to adjust the temperature of the hot water.

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.

The water heater may be configured to execute a normal operation in which a heating means is continuously operated in an ON state in a case where a required heat quantity is greater than or equal to a minimum heat quantity. The water heater may be configured to execute an intermittent operation in which the heating means is alternately and repeatedly operated in the ON state and an OFF state repeatedly in a case where the required heat quantity is less than the minimum heat quantity. The water heater may be configured to change a distribution ratio of a flow control mechanism in the normal operation and in the intermittent operation. An operating speed of the flow control mechanism in the intermittent operation may be faster than an operating speed of the flow control mechanism in the normal operation.

A control system is provided for controlling heating and/or cooling with a conditioning load such as fan coils and chilled beams. Based on user input and ambient conditions, the control system determines a desired temperature for the liquid entering the load and combines fresh supply liquid (e.g., from a chiller or boiler) with a portion of the liquid that has passed through the load, to achieve the target load input temperature for the liquid. A recirculation pump may be used to return a portion of the liquid exiting the load for mixing with the fresh supply liquid and a control valve may be used to adjust the ratio of fresh supply liquid and recirculated liquid to achieve the targeted temperature. The control systems can be compatible with a variety of liquid supply systems such as two- and four-pipe systems.

A heating and hot-water supply apparatus shortens the time taken for hot-water supply to stabilize at a set temperature in response to a request for a hot-water supply operation during a heating operation. The apparatus performs, using a common heating medium heated by a heater, a heating operation by circulating the heating medium through a heating terminal, and a hot-water supply operation of heating service water through heat exchange with the heating medium circulated through a hot-water supply heat exchanger and supplying hot water. A distribution unit (three-way valve) changes a distribution ratio of the heating medium between the heating terminal and the hot-water supply heat exchanger. A controller controls an amount of heat generated by the heater for the heating operation or the hot-water supply operation, and stops heating with the heater when the temperature of the heating medium reaches a predetermined upper-limit temperature.

The present invention provides a combustion device. In ON-OFF combustion control processing for intermittently performing the combustion operation of burners (4), a control unit (30) of a combustion device (water heater) (1), which includes the burners (4), a fuel supply unit (5), and a combustion fan (10), controls the fuel supply unit (5) and the combustion fan (10) so as to change the amount of a fuel to be supplied to the burners (4) and the number of rotations of the combustion fan (10) according to a required amount of heat for the temperature control of a target fluid (water for hot water supply) when the burners (4) are ignited to restart a combustion operation after the burners (4) are extinguished.