The steam heat exchanger uses a high steam flow rate to produce a negative vacuum suction water mixture. The conditions of use require not only a certain pressure of the steam but also a certain kinetic energy to mix. Steam ejector advantages: simple equipment, low cost, high heat utilization, and not afraid of scale. The steam heat exchanger directly injects steam into the water through a homogenous porous device. The steam pressure must be greater than the system pressure of 0.2MPa or more, the steam flow rate is not adjustable, there is noise, and the steam pressure and the system pressure overlap when opening or closing, which has certain destructive power to the heating and air conditioning system.