PURPOSE: A carbonated water purifier and a control method thereof are provided to be able to selectively discharge cold and warm purified water and carbonated water, to control the concentration of the carbonated water or the temperature of the purified water, and to clean a carbonated tank with a closed structure at ease. CONSTITUTION: A carbonated water purifier comprises a purification filter(110), a purified water tank(120), a carbonated water tank(130), a carbonic acid gas cylinder(140), a controller, a cooling device, a hot water tank, a heater, a hot water outlet, a carbonated water outlet, and a purified water outlet. The carbonated water tank, which is connected to the purified water tank with a carbonated water tank valve in between, is provided with purified water and forms a sealed room. The carbonate gas cylinder is connected to the carbonated water tank through a carbonic acid injection part, and supplies carbonic acid gas. A controller controls the purifier so that the purified water is supplied to the carbonated water tank by opening the carbonated water tank valve. The carbonated water tank is sealed by blocking the carbonated water tank valve. The purified water in the carbonated water tank is converted into carbonated water by supplying the carbonic acid gas from the carbonic acid gas cylinder to the carbonated water tank. The cooling device cools the purified water tank. The heater heats up the hot water tank. [Reference numerals] (AA) Raw water； (BB) Drained water； (CC) Purified water·；cold water； (DD) Carbonated water； (EE) Carbonic acid gas본 발명은 정수기에 관한 것으로, 보다 상세하게는 일반 정수와 함께 탄산수를 제조할 수 있는 탄산수 정수기에 관한 것이다.본 발명에 따른 탄산수 정수기는, 공급되는 원수를 정수로 필터링하는 정수 필터； 정수 필터에 연결되어 정수를 수용하며, 상단에 통기구가 마련되는 정수 탱크； 탄산수탱크 밸브를 사이를 두고, 정수 탱크에 연결되어 정수를 공급받으며, 밀폐된 공간을 형성하는 탄산수 탱크； 탄산가스 주입부를 통해, 탄산수 탱크에 연결되어 탄산가스를 공급하는 탄산가스 실린더； 및 탄산수탱크 밸브를 개방하여 탄산수 탱크에 정수를 공급받은 후, 탄산수탱크 밸브를 차단하여 탄산수 탱크를 밀폐하고, 탄산가스 실린더의 탄산가스를 탄산수 탱크에 공급하여, 탄산수 탱크의 정수를 탄산수로 변환시키도록 제어하는 컨트롤러를 포함한다.
