Abstract: A method is provided for interconnecting a single electrical heating element of a hot water heater to first and second AC electrical power sources. Typically, these first and second AC electrical power sources include a utility provided electrical power source and a renewable power source that generates AC power from DC power. The method includes operating a controller that selectively connects and disconnects the first and second power sources. If sufficient electrical power is available from the renewable power source, the utility provided electrical power source may be disconnected to preferentially utilize renewable energy.

Abstract: A water heater in which by applying pulsation of a liquid to be heated which circulates between a tank and a heat exchanger, scale that has been deposited on the inner wall (heat-transfer surface) of a to-be-heated liquid flow channel in a heat exchanger is detached, and the number of times of circulation of the liquid to be heated which circulates between the tank and the heat exchanger is controlled to be three times or less. The number of times of circulation is determined, based on the entire volume of the to-be-heated liquid stored in the tank, a boiling time to be taken for the entire volume of the to-be-heated liquid in the tank to reach a predetermined temperature, and the flow rate of the to-be-heated liquid which passes through the to-be-heated liquid flow channel.

Abstract: A heat pump water heater and systems and methods for its control are disclosed. The systems are configured to heat water within a water storage tank of a heat pump water heater wherein a controller within the system is operatively connected to a plurality of heat sources including at least one electric heating element and a heat pump and sensors in order to selectively energize one of the plurality of heat sources. The controller is configure to process data representative of the temperature of water within the tank near the top of the water storage tank, and rate of water flowing out of the water storage tank, in order to automatically selectively energize the heat sources. The selection of heat sources by the controller is determined by a mode of operation selected by the user and the data processed by the controller in view of the selected mode of operation.

Abstract: In a hot water supply system, a heat exchanger transfers heat from a heating device to inflow water to supply the inflow water at a user-set temperature. A flow sensor measures a flow rate of inflow water. A water tank stores outflow water discharged from the heat exchanger. A first temperature sensor, installed on an inlet pipe through which the inflow water flows, measures a temperature of the inflow water. A second temperature sensor, installed on an outlet pipe through which the outflow water flows, measures a temperature of the outflow water discharged from the heat exchanger. A controller includes an input unit to receive input from a user, wherein the controller controls an operation of the heating device based on at least one of: (1) comparison between the user-set temperature and the temperature of the outflow water; (2) variation in the flow rate; or (3) any combination thereof.

Abstract: A system, apparatus and method for preventing a water tank from overheating. The apparatus includes a water delivery system for delivering water to a reservoir for receiving water. The reservoir includes a level sensor and an associated heater for heating water in the reservoir. The system includes a water dispensing system for dispensing heater water from the reservoir. A controller is provided to control the operation of the system.

Abstract: Apparatus and method for providing a heated cleaning fluid to a vehicle surface. The apparatus has an inlet port for receiving an amount of fluid; an outlet port for dispensing an amount of heated fluid; a heating element that heats up fluid passing from the inlet to the outlet; and a control circuit for energizing at least a portion of the heating element with a voltage to heat the fluid passing from the inlet to the outlet.

Abstract: A water heater system includes a boiler having a supply port, an output port and a recirculation input port. A heat exchanger includes first input and output ports, and second input and output ports. An averaging tank has an inlet and an outlet. A first fluid flow subsystem is for controllably directing water along a primary loop through the boiler and from the output port of the boiler to the input recirculation port via either a first path through the first ports of the heat exchanger or a second path bypassing the heat exchanger. A second fluid flow subsystem is for directing water along a secondary loop through the second ports of the heat exchanger, through the inlet and outlet of the averaging tank, and back to the heat exchanger, whereby water directed through the secondary loop is heated from water directed through the primary loop via the heat exchanger.

Abstract: A heating apparatus comprises a plastic body and a planar heating element, together defining a liquid heating vessel. The heating element is clamped between a portion of the body and a retaining ring, the body and the retaining ring being fixed together by an induction weld. Uniform compression of a seal is obtained during the welding process. The weld provides a reliable seal.

Abstract: An electric water heater has a vertically disposed tank with a cold water inlet, a hot water outlet and at least one horizontally disposed elongated immersion heating element extending into the region of the tank between an upper region and a lower region. Each heating element is surrounded by an elongated closed end tubular sleeve having a plurality of lower openings distributed along the length of the sleeve below the heating element therein and a plurality of upper opening distributed along the length of the sleeve above the heating element. The total area of the upper openings is greater than the area of the lower openings to generate upon operation of the heating element an upwardly directed transverse flow of water in a direction from the lower openings to the upper openings along the entire length of the sleeve. A thermosiphon bypass check valve connected between the cold water inlet and the hot water outlet having a bypass conduit with one or more constrictions and a closure member.

Abstract: Apparatus for heating water intended for the preparation of hot beverages, comprising a cold-water reservoir (2) for storing unheated water and a hot-water reservoir (3) for storing heated water, wherein a heat-maintaining element (4) is accommodated in the hot-water reservoir (3), wherein the hot-water reservoir (3) comprises a draw-off tap (5), and wherein a conduit (6) is connected to the cold-water reservoir (2) which conduit opens into the hot-water reservoir (3), wherein a through-flow heating element (7) is accommodated in this conduit (6).

Abstract: A hot water tempering system for use with a standard water heater storage tank includes a heat exchanger interposed between the hot water outlet means and the cold water inlet means for transferring heat from hot water exiting from the tank to cold water entering the tank. In this way the temperature of the hot water is tempered. The system is characterized by the fact that the cold water inlet means comprises a first conduit which passes through the heat exchanger to receive heat transferred from the hot water, and a second conduit which bypasses the heat exchanger and delivers cold water directly to the tank. The two inlet conduits are connected to a cold water mains inlet by way of a diverter valve which, in response to the water temperature in the upper region of the tank apportions the water flow between the two conduits.

Abstract: A fluid heater having a fluid chamber with a base wall and an upright sidewall is positioned above a feed chamber having an upper wall. A plurality of identical tubular passage heaters, each having an upper outlet end connected to the fluid chamber base wall and an inlet end connected to the upper wall of the feed chamber, are disposed in at least one lateral protective niche recessed with respect to the fluid chamber upright wall. Return ducts located inwardly of the passage heaters connect the base wall of the fluid chambers to the upper wall of the feed chamber. Thermostatically controlled electric heating elements helically disposed on the passage heaters produce a thermosphonic circulation of fluid from the feed chamber through the passage heaters to the fluid chamber and back to the feed chamber through the return ducts. The heating capacity of the fluid heater can be varied within wide limits by energizing different numbers of passage heaters.

Abstract: An electric water warming system generally comprises a cylindrical first water storage tank to be installed in a vertical fashion, a water feed pipe connected to a bottom portion of the first water storage tank for feeding water therein, and a hot water flow-out pipe connected to a top portion of the water storage tank for flowing out hot water therefrom. A temperature of hot water stored in the water storage tank is detected by a detecting device at a plurality of levels thereof and a water feed side and a water flow-out side are connected through a circulation pipe. A second water storage tank is incorporated in the circulation pipe and a heater is disposed in the second water storage tank. A temperature of the hot water in the second tank is detected by another detecting device disposed at an outlet portion of the second water tank. A circulation pump is incorporated in the circulation pipe at a portion upstream of the second water storage tank.

Abstract: An electric water heater has a vertically disposed tank with a cold water inlet, a hot water outlet and at least one horizontally disposed elongated immersion heating element extending into the region of the tank between an upper region and a lower region. Each heating element is surrounded by an elongated closed end tubular sleeve having a plurality of lower openings distributed along the length of the sleeve below the heating element therein and a plurality of upper opening distributed along the length of the sleeve above the heating element. The total area of the upper openings is greater than the area of the lower openings to generate upon operation of the heating element an upwardly directed transverse flow of water in a direction from the lower openings to the upper openings along the entire length of the sleeve. A thermosiphon bypass check valve connected between the cold water inlet and the hot water outlet having a bypass conduit with one or more constrictions and a closure member.