... to 2 minutes, then open any hot water tap point, the hot water will be out ,4,over-time ... and practical features: A, to save cold water of hot water pipe; B,Saving a lot of time to release ... the cold water of the pipe; C, when we need to use hot water ,it will work ... button and the " " button, set the appropriate water temperature (system hot water temperature is 40 °C, Can choose between 25- ...