Intermatic WH21 Electric Water Heater Timer
Intermatic's Electric Water Heater Timer Switch will automatically schedule hot water when needed. This time switch will repeat a preset schedule daily except when the external manual push button is used.  This manual button permits the user to turn the water heater on and off ahead of the schedule.  The time switch will resume the reset program by the next scheduled operation.  This devise turns the water heater on during high use periods; off during low use periods.  It has up to 12 on/off settings per day.  The capacity is 25 amps, (6250) 250 volts, 60 Hz.