Below we introduce a concept - Reynolds experimental principle. There is a strange phenomenon in nature. The ocean currents have cold currents and warm currents. When these two ocean currents meet, there will be obvious stratification, and they will not be completely mixed together. Scientists made simulation and analysis of this natural phenomenon, which was called Reynolds experimental principle. The R&D personnel simulated this natural phenomenon based on the Reynolds experimental principle. The precision control valve allows water to enter into water tank at a certain flow rate from the bottom, and water level sensor controls water intake. When influent water reaches a certain amount, water is stopped and starts to be heated until reaches the set temperature, then inlet water control valve automatically opens and feeding water into water tank again. Because the proportion of cold water is greater than hot water, cold water will gradually support hot water to go up. Meanwhile, water inlet control valve automatically closes, and start to heat the cold water until it reaches set temperature again. This cycle continue to repeat until the water reaches the highest water level in tank. That means, a work cycle is completed. This technology greatly improve the efficiency of hot water production and have sufficient hot water supply, at the same time, energy consumption is reduced significantly.