Single Sprinkler Head Not Working: Blockage Diagnosis

One head in a six-head L-shaped zone has no flow. You've replaced the head—no change. Minimal water trickles from the riser when the zone runs. Since other heads work, the issue is a localized blockage in the lateral line or fitting feeding that head.

Step-by-Step Blockage Hunt

1. Dig down to the riser. Unscrew the nipple from the fitting on the lateral line.
2. Inspect the fitting (usually a tee or elbow) for rocks, roots, or debris. Remove any visible blockage with a screwdriver or wire.
3. If clear, trace the pipe backward toward the previous fitting. Dig at each joint (tees, elbows) and repeat the inspection.
4. Cut out and replace any fitting that's clogged beyond cleaning.

Why This Happens Mid-Line

Debris enters during repairs or from deteriorating pipe. It settles at the first restriction—often a fitting reducer or a sharp bend—blocking only downstream heads.

No Shortcut

There's no non-invasive fix. You must expose the pipe and fittings sequentially until you find the obstruction. Start at the dead head and work backward.

Persistence pays off—once cleared, the head will perform like the others. Good luck!