PROBLEM TO BE SOLVED: To provide a storage water heater improved in cleaning effect.SOLUTION: The storage water heater includes a circulation pipe conduit disposed to be returned to a bathtub from the bathtub through a heat exchanger a bath-side water pump for circulating bath water in the circulation pipe conduit an ejector for circulation for generating fine bubbles, disposed at an upstream side with respect to the heat exchanger of the circulation pipe conduit an ejector air solenoid valve for circulation opening and closing an air intake section connected to the ejector for circulation and a control means for operating the bath-side water pump in a pulsational manner so that a production amount of fine bubbles is periodically changed by alternately repeating a high rotation state and a low rotation state in the bath-side water pump, in cleaning the inside of the heat exchanger and the circulation pipe conduit by circulating the bath water including the fine bubbles produced by the ejector for circulation.COPYRIGHT: (C)2011,JPO&INPIT【課題】洗浄効果を向上させた貯湯式給湯機を提供すること。【解決手段】浴槽から熱交換器を通って浴槽に戻るように配置された循環管路と、循環管路内の浴水を循環させる風呂側送水ポンプと、循環管路の熱交換器よりも上流側に配置された微細気泡発生用の循環用エジェクタと、循環用エジェクタに接続された空気取入れ部を開閉する循環用エジェクタ空気電磁弁と、循環用エジェクタで生成される微細気泡を含んだ浴水を循環させることによって熱交換器及び循環管路の内部を洗浄する際に、風呂側送水ポンプが高回転状態と低回転状態とを交互に繰り返すことによって微細気泡の生成量が周期的に変化するように、風呂側送水ポンプを脈動的に動作させる制御手段と、を備える。【選択図】図6
