To set an Intermatic wall switch timer, erase the earlier timer settings, set the time dial in half-hour increments, set it to the current time, position the dial in the On and Off settings, and press it to set the time. Turn the time dial until a red light blinks.
To erase the previous settings on the Intermatic wall switch timer, note the Off setting, and push the control lever left. The red light of the indicator now switches off, indicating the earlier settings are deleted. Slide the control lever towards the On setting. The red light starts to blink again.
To set the time dial in half-hour increments, rotate it clockwise until the 30-minute mark closest to the present time is reached. To set the time dial to the current time, press it. This causes the red light to shut off.
To set the on and off timings, twist the time dial clockwise until the first On setting is reached. Do the same to program the first Off time. Repeat this process until all desired on and off timings are programmed.
Finally, turn the time dial clockwise until the red light is on, indicating the Intermatic wall switch timer is in Automatic mode. The timer can now control lights as per the set on and off timings.