A timer for monitoring the use of hot water in the home to conserve energy is shown. The entire timer apparatus is enclosed inside the hot water control knob so that when the control knob is rotated to turn ON the hot water, the timer is activated. After predetermined time intervals, various visual and audio alarms are given, the alarms thus encouraging the conservation of energy by using less hot water. Also, the timer monitors the number of times the hot water has been used during a given period of time, such as a month or year. The timer, in addition to its primary energy saving function, is ideally suited for use as the hot water control knob of a bathroom shower.