A circulating heating water heater includes a circulating heating system which further comprises a housing, a circulating pump, a heater, a water inlet pipe and a water outlet pipe; the circulating pump and the heater are arranged inside the housing, and a water inlet of the circulating pump communicates the water inlet pipe with the water inlet of the heater via a water inlet tee valve; a water outlet of the circulating pump communicates the water outlet pipe with a water outlet of the heater via another water outlet tee valve; the water outlet pipe and the water inlet pipe extend to an outside of the housing.