On-demand water heating system

A water heating system for providing water on-demand at consistent desired precise temperatures comprising:

• a closed loop assembly including
• an electric heating system with heating elements in a plurality of heating chambers,
• an air separation chamber with an air vent valve to evacuate air from a closed loop,
• a circulation pump of sufficient size to create a flow around and within the closed loop of a rate of 4-6 times of flow in and out of the system,
• a small water accumulation tank that is less than a six gallon capacity without an internal heat source,
• a flow indicating sensor used to verify that the closed loop has a minimum of a threshold flow rate within the closed loop,
• an expansion tank with a bladder to provide thermal expansion space,
• with plumbing forming the closed loop
• in conjunction with
• a system inlet with an inlet pressure regulator to regulate the pressure of the incoming water to the closed loop;
• an incoming temperature sensor after the system inlet in the closed loop;
• a system outlet that allows heated water to exit the closed loop;
• a water feed temperature sensor in the closed loop adjacent to the system outlet, which measures the temperature of the water just before the water exits the closed loop;
• a heater temperature control sensor after the heating system in the closed loop for measuring temperature of the water as it exits the heating system;
• a combined feed forward and feed back temperature control system being a microprocessor programmable logic controller that receives input from the flow indicating sensor, the incoming temperature sensor, the heater temperature control sensor, and the water feed temperature sensor to precisely adjust intermittently outgoing water temperatures by immediately controlling the amount of voltage to the heating elements to heat the water at precisely a usage temperature within a deviation of ±2° F.;
• and
• a check valve in the closed loop between the system inlet and the system outlet that avoids incoming water from being mixed with heated outlet water wherein the system does not use cool water to mix with heated water in mechanical thermostatic mixing and the water is not heated more than ±2° F. of the desired temperature.