A liquid heater may heat liquid using at least one of an electric heater or a hybrid heat pump. The liquid heater includes a tank to store liquid, an insulator at an outer surface of the tank, and a case surrounding the insulator. The case includes a first outer panel, a second outer panel, and a cover panel fastened between the first outer panel and the second outer panel. The cover panel is detachable from the liquid heater to access electronic devices such as a controller for the electric heater.

A boiler includes a tank, a gas circuit that includes a main combustion chamber in the tank and branch tubes in the tank that extend off of the main combustion chamber, and a water circuit fluidly isolated from the gas circuit. The water circuit includes a first manifold and water tubes that extend off of the first manifold. Each water tube extends through a respective one of the branch tubes, which may serve to preheat the water prior to discharge of the water into the tank.

A water heating system is provided. The water heating system includes a tank having a wall, a water inlet defined through the wall and configured to allow ingress of water into the tank, and a water outlet defined through the wall and configured to allow egress of water from the tank. The water heating system also includes a heating element disposed within the tank, having a substantially elongate shape, and being moveable between a first inclination angle with respect to a base of the tank and a second inclination angle with respect to the base of the tank.

Provided is a hot water supply tank including: a case forming an appearance of the hot water supply tank; a heating container accommodating a fluid and having an inner side treated with anticorrosive; a heater installed on an outer side of the heating container and transferring heat to the fluid; and a heat insulator interposed between the case and the heater, wherein in a predetermined volume of the heating container, a ratio at which a performance of the heater to transfer heat (hereinafter, heat transfer performance) is maximized (hereinafter, optimum ratio) among the ratios of side height to bottom diameter of the heating container (hereinafter, aspect ratios) is determined by whether the heater is installed on the bottom as well as side of the heating container, and determined based on an area of the heating container occupied by the heater (hereinafter, heat transfer area).

The present invention is directed to an integrated boiler system, comprising: two separate boilers, one disposed inside the other, each of the boilers having: (a) a vertical partition disposed therein; (b) a water passage at a top side of the partition; and (c) a water passage at a bottom side of the partition; a chamber disposed in, or generated by, a gap between the boilers; and a heating element, disposed in the chamber, for heating the boilers simultaneously by the same energy.

A system for hot and cold water supply to consumers that includes photovoltaic solar panel, wind turbine, water heating tank, water tank and cooling system. The heating tank includes an electrical connection mechanism, an outer layer, a water bag and heating carpet that is positioned in a dry space between them. The water tank includes an outer layer and a water bag. The electrical connection mechanism connects the heating carpet and the cooling system to the photovoltaic solar panel and to the wind turbine. The volume of the heating tank or the water tank are larger than the volume of the average hourly hot or cold water consumption of the consumer. The system is able to supply hot and cold water also at times that the photovoltaic solar panel and the wind turbine do not produce electricity.

A liquid heater may heat liquid using at least one of an electric heater or a hybrid heat pump. The liquid heater includes a tank to store liquid, an insulator at an outer surface of the tank, and a case surrounding the insulator. The case includes a first outer panel, a second outer panel, and a cover panel fastened between the first outer panel and the second outer panel. The cover panel is detachable from the liquid heater to access electronic devices such as a controller for the electric heater.

A solar water pasteurizer has a water jug removably disposed in a solar box with insulation and a solar window. The water jug has a lid to close an aperture in the solar box and a handle thermally isolated from the water jug to facilitate handling of the water jug with heated water. Multiple water jugs can be swapped in and out of the solar box. The solar box also has a thermal mass to preserve some heat in the solar box.

A hot-water supply apparatus capable of restraining the occurrence of noises from a building wall surface side includes a hot-water supply apparatus main body having a burner and a heat exchanger that generates hot water by combustion exhaust of the burner, and a rectangular parallelepiped main body case that houses the hot-water supply apparatus main body. A back plate (5c), which closes the back side of the main body case, is installed to a building wall surface (W) such that the back plate (5c) opposes the building wall surface (W) with a predetermined void space (S) provided therebetween. A soundproof member (18), which closes at least a part of an open end of the void space (S), is provided on the main body case (5).

There is provided a method of producing an exterior case for a hot water unit including a pressing process in which press processing is performed on a flat metal plate, and a component part of an exterior case used for accommodating a hot water device for hot water production or hot water storage therein is formed; and a painting process in which any of letters, symbols, figures, and patterns is painted on the component part of the exterior case, wherein the painting process includes an ink jet printing process in which ink jet printing is performed on the flat metal plate and an ink jet printing layer is formed, and wherein the pressing process is performed after the ink jet printing process.