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 hydraulic heating apparatus is provided having a power control system and a power supply electrically coupled to the power control system. One or more heating elements are provided and electrically coupled to the power control system. A first sensor is electrically coupled to the power control system for measuring incoming water temperature to the heating system. A second sensor electrically is coupled to the power control system for measuring outgoing water temperature from the heating system. A third sensor is electrically coupled to the power control system for measuring incoming water flow to the heating system. The power consumption of the heating apparatus is managed by the data collected and analyzed from the sensors by a central processing unit and a preset temperature inputted by a user interface circuit.