A system and approach for developing a periodic water usage profile and demand for controlling a water heater. A mode may be selected for demand for a certain amount of water of a particular temperature range to be available for use from the water heater. Data on hot water usage may be collected and the usage profile and demand may be calculated from the data. The water heater may be programmed to operate in a certain fashion based on the usage profile and demand. A control knob may be on the water heater control to select a particular demand. Control of the water heater may be operated from a remote device connected in a wireless or wired fashion. An optimization program may be implemented in the control of the water heater for achieving one or more beneficial goals related to water heater performance and hot water production.

A water heating assembly, related kit, use and method make use of a temperature control near a point of use of water, so as to reduce a time response for hot water at this point of use are provided. The water heating assembly includes a tank for containing water, an inlet temperature sensor for sensing an inlet temperature of the water upstream of the tank, and a valve located upstream of the tank. The valve is actuated when the sensed inlet temperature reaches a given temperature set-point such that the water is bypassed from the tank and directly sent to the point of use. The water heating assembly is configured such that the point of use can be fed with water at the desired temperature in a reduced time, the water coming directly from the hot water source and/or the water heating assembly, thereby saving water, energy and time.

A water heater includes an inner water tube coil and an outer water tube coil separated by a drum baffle. The inner and outer coils extend above a top edge of the drum baffle by at least a full turn of each coil. A flue gas bypass path is defined between a top edge of the drum baffle and a top insulation layer above the inner and outer coils. Flue gases flow radially though the inner coil, up along the drum baffle, through the flue gas bypass path, and downwardly over the outer coil to heat water flowing through the inner and outer coils. The water flows into the outer coil at the bottom of the coil, winds upwardly through the outer coil in countercurrent flow with respect to the flue gases, then down through the inner coil.

A hot water supply apparatus includes: a first channel configured to send water in a medium-temperature layer (M) to a heating section; and a second channel configured to return water heated by the heating section to a tank. The second channel has an outflow port at a lower position than an inflow port of the first channel.

A method of operating a gas heater for water including the steps of restricting a water flow to the gas heater; determining a first rate of a first gas heating for the restricted water flow; adjusting the gas heating to the restricted water flow; repeating the previous steps until a heated water has a temperature above a temperature threshold; removing the restriction to the water flow to increase the water flow; and determining a second rate of a second gas heating for the increased water flow.

Disclosed are system 100 and method of energy efficient hot and cold water management. The system 100 comprises: a control unit 101 for dynamically controlling the functioning of the system 100; at least a water storage tank 102 with at least one of a water level sensor, at least a heating element 1021, at least a temperature sensor 1022 or any combination thereof; at least an auxiliary water storage tank 103 with at least one of a water level sensor, at least a temperature sensor 1032; at least a water mixer unit 105 having at least a temperature sensor 1051; a user interface unit 1012 for controlling and monitoring different parameters including temperature, water level, opening and closing of valves 108 and 109; and a power supply with power backup unit 104 for providing basic power for proper functioning of the system 100.

A closed-loop temperature controller employing at least two sensors: a control temperature sensor and a safety sensor at the heat-transfer element. The heat-generating element is separated from the controlled mass/volume by a transport delay so that the mass or volume that is being heated or cooled is located in a vessel which is located remotely from the heat-transfer unit. Thermally conducting fluid flows through a conduit that connects the heat-transfer unit to the vessel. Upon fluid flow interruption or control sensor removal, the temperature controller quickly detects thermal runaway before the safety sensor has reached the critical temperature. In heated systems, the temperature controller will therefore minimize direct damage and/or overshoot damage caused by excessive heat. It will also maintain the heater's output at an elevated, but non-damaging level to enable a fast recovery to the original setpoint temperature after the nonlinearity subsides.

The disclosed technology includes an on-demand water heater which uses an electric heat source to heat the water. The on-demand water heater can have a low fluid capacity heating chamber which has an inlet and an outlet, an electric heat source for heating the water, and a controller to control the electric heat source and maintain the temperature of the water at a predetermined temperature setting. The on-demand water heater can be powered by a direct current power source. The on-demand water heater can also utilize a solar thermal system to provide additional heat to the water.

An electric integrated circuit water heater apparatus includes: a cold water inlet for allowing input of cold water into a storage tank with heating elements comprised of integrated circuits configured to exchange heat from the heating elements to the water in the storage tank through a heat exchanger, in which heat produced by running the integrated circuits is recovered into the heat exchanger, thereby heating the stored water by using heat from the integrated circuits. A hot water outlet is provided in the upper portion of storage tank such that the water will have passed all of the heating elements prior to exiting the hot water outlet.

A rotor is a rotor for a pump. The rotor includes a rotor core having a magnet insertion hole and having an annular shape about an axis, a permanent magnet inserted in the magnet insertion hole, and a rotor cover surrounding the rotor core from outside in a radial direction about the axis. The rotor core has a first core portion disposed on an inner side of the magnet insertion hole in the radial direction, a second core portion disposed on an outer side of the magnet insertion hole in the radial direction, and a hole separating the first core portion and the second core portion from each other. The rotor cover has a positioning portion that positions the first core portion and the second core portion in a circumferential direction about the axis.