Immersed steam-water mixer is an energy-saving steam heater, which has the advantages of fast heating speed, good noise elimination effect and easy heating of cold (liquid) water to boiling point. Due to the adoption of a brand-new noise elimination structure, the noise is reduced to below 50dB, which solves the problems of high cost, large noise, occupation of computer room area and heavy installation workload of traditional heating methods. It can be linked with intelligent automatic water temperature controller and automatic liquid level control alarm device, and is a fully automatic hot water preparation system.