Adjustable constant-temperature constant-flow water heater

The utility model relates to an adjustable constant-temperature constant-flow water heater, comprising a shell, an insulation layer, an inner bag, a heating pipe, a water inlet pipe, a water outlet pipe, a power supply control board and an operation control board, wherein a safety valve, a booster pump, a flow sensor, an opening valve, one inner bag, a temperature control valve, a first temperature sensor and a normal closed solenoid valve are connected in series between the water inlet pipe and the water outlet pipe, the operation control board is bidirectionally connected with the power supply control board; the power supply control board respectively directly controls the booster pump, the normal closed solenoid valve and the heating pipe; the power supply control board controls the opening valve by a first micro motor and the temperature control valve by a second micro motor; the power supply control board respectively receives the sensing signals from the flow sensor, the first temperature sensor, a second temperature sensor and a water-level sensor. The closed-ring circuit control is used to accurately ensure the constant-temperature constant-flow water from the water heater even though in low water pressure and the manual adjustment is also not needed. The adjustable constant-temperature constant-flow water heater has the following advantages of convenient and comfortable use, energy saving and humanization.