Abstract: A multiple-in-one heating unit is provided with a means to set a power capacity level from one of multiple choices at which a circuit board draws input power thereby establishing an output power level from the circuit board to generate a prescribed heat capacity. For example, for a 3-in-1 heating unit, the power capacity level is set by a 3-in-1 DIP Switch which can furnish one of three different signals (e.g., PA0, PA1, and PA2) to a control chip. The control chip will manage a relay group or another type component signaling for generating one of three different capacity outputs.

Abstract: A tankless heater includes at least one non-metallic tube, at least one heating layer on or adjacent an external or internal surface of the tube, and a controller to generate a signal to be applied to the heating layer. The signal from the controller is applied through one or more electrodes coupled to the heating layer, and the heating layer generates heat in response to the signal. The heat is then transferred to a liquid flowing through, a gel located within, or a solid inside of the tube to heat the liquid, gel, or solid to certain temperature range, which may or may not be predetermined. Or, the heat is transferred to a liquid, a gel or a solid around the tube to heat the liquid, gel or solid to certain temperature, which may or may not be predetermined. In a multiple-tube configuration, the tubes may be independently selected and may have different temperature ranges. Also, according to one arrangement, no heating element is included inside any of the tubes.

Abstract: A tankless water heater comprising a pipe, at least one coil around the pipe, at least one heating element located within the pipe and responsive to an electromagnetic field generated by the coil, and a controller to apply an alternating current (AC) signal to the at least one coil, the AC signal applied at a predetermined frequency and magnitude to cause the heating element to heat water flowing in the pipe to a predetermined temperature through induction heating.