A heater includes a flow guide and a plurality of electrical resistance heating elements. The flow guide defines a continuous geometric helicoid disposed about a longitudinal axis of the heater assembly. The flow guide defines a predetermined pattern of perforations that extend in a longitudinal direction through a first longitudinal length of the geometric helicoid, the longitudinal direction being parallel to the longitudinal axis. The plurality of electrical resistance heating elements extend through the perforations. At least one electrical resistance heating element of the plurality of electrical resistance heating elements has a first region with a first watt density and a second region with a second watt density. The second region is located farther in the longitudinal direction than the first region. The second watt density is less than the first watt density.

A modular manifold for a tankless water heater includes a first cavity member having a first opening, a second opening, and a base wall; a second cavity member coupled to the first cavity member, the second cavity member having a first opening, a second opening, and a base wall; a first cover plate coupled to either the first cavity member or the second cavity member; and a second cover plate coupled to either the first cavity member or the second cavity member, wherein two openings in the first and second openings are covered by the first and second cover plates, respectively, and wherein the base walls of the first and second cavity members, the first and second cover plates, and the two openings in the first and second openings not covered by the first and second cover plates define a fluid flow path in the modular manifold.

The present invention provides an electric boiler having a heating element surrounded by a thermally conductive inner container to define an inner passage about the heating element, the inner container having an inlet 13, 14 and an outlet for a flow of water and is arranged such as to cause water received at the inner container inlet to flow along the inner passage in close proximity to a surface of the heating element, the boiler further comprising an outer container in which the inner container is substantially located, the outer container defining an outer passage about at least part of the inner container, the outer container having an outlet into the inner container wherein the outer container is arranged such as to cause water to flow along the outer passage in close proximity to a surface of the inner container, such that water received in the boiler makes at least a double pass through the boiler to increase the potential heat transfer to the water.

The present application discloses an electric vehicle, and a heating cavity assembly of an electric heater of the electric vehicle. The heating cavity assembly includes: an electric heating unit, located in a heating cavity and configured to convert electric energy into heat energy; a flow channel structure, located in a heat exchange cavity, configured to allow a heat transfer medium passing through the flow channel structure to receive heat energy from the electric heating unit and including a plurality of medium flow channels, wherein the plurality of medium flow channels extend in parallel to each other along respective extension track lines with a translation relationship.

A heat exchanger for fluids includes an elongated conduit. At least two spaced fluid passageways are defined in the conduit and extend longitudinally through the conduit from a first end thereof to a second end thereof. A heat transfer element thermally contacts a surface of the conduit to transfer heat to or from a fluid flowing through the at least two spaced passageways. The conduit can be unitary and of one piece. In one embodiment, the conduit can be a single crystal.

When a voltage signal is input to input terminals as a positive voltage, the voltage conversion circuit generates a control voltage proportional to an input voltage by a voltage-dividing circuit according to resistance elements, a voltage follower circuit according to an operational amplifier, and a voltage-dividing circuit according to resistance elements. When a voltage signal is input to the input terminals as a negative voltage, since the operational amplifier outputs a power supply voltage according to an input of the negative voltage, the voltage conversion circuit generates a predetermined positive voltage obtained by dividing the power supply voltage by the resistance elements as the control voltage. The predetermined positive voltage is higher than a voltage range of the control voltage when the voltage signal is input as the positive voltage.

An apparatus, method, and device for heating water using in-line magnetic induction. The heating system utilizes eddy currents created via one or more magnetic fields acting upon a stationary ferrous core. The device can be housed within an enclosure, which can in turn be connected to any existing water line, and can be connected to basic house voltage. During operation, cold water enters the enclosure, passes through the system, and leaves the system at a desired temperature setpoint greater than the initial inlet water temperature.

The invention is directed to a liquid heater for rapidly heating a liquid without overheating the liquid. The liquid heater comprises a liquid flow channel having a passage through which liquid flows, a heating part disposed outside the liquid flow channel, a heat reflecting part facing a heat radiating side of the heating part, and a cooling part through which a cooling medium flows adjacent a reverse side of a reflecting surface of the heat reflecting part for cooling the heat reflecting part. Radiant heat not absorbed in the liquid is reflected by the heat reflecting part. The heat reflecting part reflects radiant heat cooled by the cooling part so that the body of the liquid heater and peripheral members are maintained at a temperature not higher than a predetermined temperature to prevent overheating the liquid.

The invention relates to a device for heating a fluid (2), comprising a heating body (4) having a through passageway (6, 8) for the fluid and provided with at least one groove (14) on its outer surface; at least one electrical resistance (24) housed in the at least one groove (14) of the heating body. The device further comprises at least one closure plate (20) of the at least one groove (14) overlying the at least one resistance (24).

The invention provides a device (200, 300, 400) for heating a continuous flow fluid. Said device (200, 300, 400) consists of a steel conduit (3, 3′, 3″) through which the fluid to be heated flows and of at least one sheathed resistor (2, 2c, 2d, 2e, 2f) that is parallel to the steel conduit (3, 3′, 3″) and that is in thermal contact therewith. The steel conduit (3, 3′, 3″) and the at least one heating element (2, 2c, 2d, 2e, 2f) are incorporated in a die-casting element made of an aluminium alloy.