The paper introduces an example and its running data of applying conditioning-controlling water-water ejector heating unit developed by the author in heating system. It proves that: the hydraulic stability of the system is very good. When heating medium of heat source and heat consumer are respective high-temperature water and low-temperature water, the hydraulic stability of the heating system is close to 1; when the flow of any consumer of heating network changes, the flow and heating quality of other consumers are almost unchanged.