- Certified Irrigation Technician System Maintenance and Repair Flashcards

A customer reports that one zone has significantly lower water pressure than all other zones. After confirming adequate supply pressure, the technician should investigate:

Answer: The zone valve for partial obstruction, a leak on the zone's lateral line, or a partially closed isolation valve

Low pressure isolated to one zone while others are normal indicates a zone-specific problem: the zone valve may be partially obstructed by debris, there may be a pipe leak on the lateral losing water and pressure, or a manual shutoff valve may be partially closed.

When adjusting a rotor sprinkler's arc (coverage pattern), the technician should:

Answer: Use the manufacturer-specified adjustment method — typically a flat-blade screwdriver or special key to set the left stop and adjust the arc range

Rotor arc adjustments are made using the manufacturer's specified tool and method, which typically involves setting a fixed left-side stop point and adjusting the arc range with a screw or key. Each manufacturer has a specific procedure documented in their installation guides.

Clogged drip emitters can often be cleared by:

Answer: Flushing the lines by opening the end caps, and for individual emitters, soaking in a mild acid solution or replacing them

Clogged drip emitters are addressed by first flushing the lateral lines (opening end caps to flush accumulated sediment), then individually cleaning or replacing emitters that remain clogged. Soaking in a mild acid solution (vinegar or muriatic acid mix) dissolves mineral deposits.

A mainline pipe has cracked and is leaking. For a permanent PVC repair, the technician should:

Answer: Cut out the damaged section, install a new piece of pipe with slip couplings (or a union on one side), prime and cement all joints, and allow proper cure time before pressurizing

A proper PVC repair requires cutting out the damaged section, using a new pipe section with slip couplings (since compression couplings or a union accommodate the fixed length), and making solvent-cemented joints. The repair must cure before the system is pressurized.

A rain sensor has been installed but the system still runs during and after rain events. What should the technician troubleshoot?

Answer: The sensor connection to the controller — verify it is wired to the sensor terminals and the controller's rain sensor bypass switch is in the 'active' position

If the rain sensor is not overriding the controller, check: (1) that the sensor is properly wired to the controller's sensor terminals, (2) that the controller's sensor bypass switch is set to 'active' (not 'bypass'), and (3) that the sensor itself is functioning (test by pressing the spindles manually).

What maintenance should be performed on a backflow prevention assembly at least annually?

Answer: A certified backflow test by a licensed tester to verify all internal components are functioning within specifications, with results reported to the water purveyor

Backflow assemblies must be tested annually by a certified tester using a differential pressure test kit. The test verifies that check valves maintain proper differentials, the relief valve (on RPZ) opens at the correct pressure, and all components pass minimum standards.