If an electronic timer malfunctions or you want to water without reprogramming the timer's cycle, you can override the programming or turn on the sprinklers the old-fashioned way with the twist of a knob. Although operating sprinkler knobs is easy, many homeowners have difficulty locating the valves. Sprinkler valves are often hidden beneath utility boxes, called sprinkler boxes, concealed behind tall grass or covered with dirt. If you check the perimeter of your home and yard, you can find your sprinkler system's valves and put them to use.
Override Timer Programming
Open the sprinkler timer control panel cover. To override the programmed irrigation schedule, press the timer keypad or turn the timer dial to select the irrigation zones that you want to activate. Electronic sprinkler timers often control multiple valves, sorted as "zones." To activate the entire system, select all zones.
Press the control panel button labeled "manual cycle" or use the keypad to navigate through control options and select the "manual cycle" option. Although timer controls vary according to the make and model of the time, most timers use the zone selection and "manual cycle" commands to manually activate a sprinkler system.
Close the timer's control panel and go to the zones that you are irrigating. Check the zones to make sure the sprinklers are on.
Manual Sprinkler Valve Operation
Walk the perimeter of the house to search for sprinkler valves. Landscapers frequently install valves beside an exterior wall, near garage doors, entry doors or within planter boxes. Look for rectangular, plastic boxes that protrude slightly from the ground surface. The boxes, called irrigation valve boxes, often contain sprinkler valves. If you cannot locate them around the house exterior, walk the perimeter of the yard. Alternatively, follow the wires from the sprinkler timer to the valves, since timer wires always run from the timer to the timer-controlled valves.
Locate the manual control knob on the top of the sprinkler valve. Timer-controlled valves sometimes have a single, bolt-like rod that serves as a manual knob. If you are working with a timer-controlled valve, do not turn the cylindrical, wire-connected solenoid. Other valves have a cross-shaped handle or round knob.
Attach pliers or an adjustable wrench to the rod-like knob found on some timer-controlled valves. Turn the pliers or wrench counterclockwise to open the valve. If you have a cross-shaped valve handle, stick the prongs of a sprinkler valve key around the cross and turn the key counterclockwise to activate the valve. For round knobs, grip the knob with your hand or a clean rag and turn counterclockwise to activate.