The concepts relate to reducing energy loss associated with hot water systems. One example is manifest as a system with an automatic hot water recovery apparatus and selective hot water isolation devices. In one example a selective hot water isolation device is configured to be connected in fluid flowing relation with a first water line and a second water line and the selective hot water isolation device is configured to control water cross-over from the second water line into the first water line based upon water flow through the first water line.

A hot water heater appliance includes a boiler, a companion water heater and a controller. The controller is configured to control the water heater appliance in response to a scheduled plurality of performance modes based on a preset schedule. A first performance mode is scheduled to be performed at an expected low usage time and a second performance mode is scheduled to be performed at an expected high usage time relative to the expected low usage time.

Provided is a faucet device for an aircraft lavatory unit, wherein a second joint and a third joint are joined by inserting the third joint of a heater module into a second joint of a valve module, and screw members are used to fasten a first case and a second case. As a result, the valve module and the heater module are joined in series via the second joint and the third joint. A first connector of a controller module is joined to a third connector of the valve module and a second connector of the controller module is joined to a fourth connector of the heater module. The first joint of the valve module is joined to a water supply pipe. A fourth joint of the heater module and a faucet main body are joined via a pipe.

Disclosed is a method of mapping an in-building water supply installation having multiple controllable water outlets, the installation including a supply of water; in a water flow path between the supply of water and the controllable water outlets, a flow measurement device and a flow regulator; a processor being operatively connected to the flow measurement device and the at least one flow regulator. The method comprises opening a first of the water outlets and processing signals from the flow measurement device with the processor at least until a first flow characteristic is determined; closing the first of the water outlets; repeating the opening, processing and closing operations for each of the other water outlets to determine for each controllable water outlet a respective flow characteristic. Subsequently the processor is configured to; identify the opening of a particular one of the plurality of controllable water outlets based on the similarity of a detected flow characteristic to a respective flow characteristic; and control said at least one flow regulator, based on the identification, to control a supply of water to the identified controllable water outlet.

A compressor unit providing heat for human use including a combustion housing defining a combustion chamber therein, a magnetic intake valve providing the source of air used in the combustion chamber, and an exhaust valve providing an exit path for exhaust gasses, wherein the exhaust valve can be a pivot exhaust valve, mounted to a combustion pipe wherein an explosive reaction occurs, an igniter operatively attached to the combustion housing, a release valve arranged within the exhale port of the compression housing, a fuel injector operatively attached to the exhale port, a compression housing defining a compression chamber spaced from the combustion chamber and disposed in fluid communication with the combustion process, a half-pipe attached to the compression housing, and a magnetic oscillation unit with an oscillation plate supported on a back and forth moving center piece.

A low pressure drop water heating system comprising a cold side conductor having a receiving end and a closed end; a hot side conductor having an exit end and a closed end; a pump; a bypass conductor having a first end and a second end, wherein the first end is adapted to the receiving end and the second end is adapted to the exit end; at least one heat exchanger having a flow valve; a heat exchanger inlet temperature sensor disposed on the inlet of one of the at least one heat exchanger; an outlet temperature sensor disposed at an outlet of the at least one heat exchanger closest to the exit end; a system outlet temperature sensor disposed on the exit end and a system inlet temperature sensor disposed on the receiving end.

A device and water system for preventing the proliferation of living beings in the water pipes of buildings and that can be applied to taps with a supply of hot and cold water to improve the health standards of public and private constructions with hot water circulation systems, or without, by recirculation within the hot, warm or cold water system. The same permits the prevention of the freezing of the piping. The device has a bypass between the hot and cold water pipes that supply a tap, with a pump that causes recirculation of the water via the bypass, a mechanism for regulating the flow of water located in the bypass, a temperature probe in the water pipe above the bypass, a mechanism for activating and deactivating the pump, and a system for controlling the flow regulation mechanism, the activation and deactivation of the pump and functioning of the pump.

An aircraft water supply system supplies water to a water discharge port in an aircraft. A cold water flow path supplies cold water to the water discharge port. A hot water flow path supplies hot water to the water discharge port. A first control valve adjusts the flow rate of cold water flowing through the cold water flow path. A second control valve adjusts the flow rate of hot water flowing through the hot water flow path. A temperature sensor detects the water temperature at any point up to the water discharge port. A flow control unit controls the opening/closing state of the first control valve and the second control valve based on the water temperature detected by the temperature sensor.

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.

A water heater system having a running water inlet through which running water flows in and a hot water outlet through which hot water heated in a heat exchanger is discharged is disclosed. The water heater system may include a first connection pipe connecting a gap between the running water inlet and an entry of the heat exchanger, a second connection pipe connecting a gap between an outlet of the heat exchanger and the hot water outlet; a bypass pipe connecting a gap between the first connection pipe and the second connection pipe, a bypass valve installed to the bypass pipe so as to control the direction of water flowing through the bypass pipe, and a controller, in a hot water usage mode, controlling the bypass valve so that the water moves from the first connection pipe to the second connection pipe through the bypass pipe, and in an inner circulation mode, controlling the bypass valve so that the water moves from the second connection pipe to the first connection pipe through the bypass pipe.