How to Adjust Sprinkler Heads for Optimal Coverage
Properly adjusted sprinkler heads can reduce water waste by 30% while ensuring your landscape gets the coverage it needs. Learn to eliminate overspray onto hardscapes, fix dry spots, and optimize your irrigation efficiency with these simple techniques.
Why Proper Adjustment Matters
Misaligned sprinkler heads waste 25-50% of water through overspray and evaporation. In Arizona's climate, proper adjustment can save $30-80 per month on water bills while keeping your landscape healthier.
Tools Needed
- Flat-head screwdriver or sprinkler adjustment key
- Pliers (for stubborn adjustments)
- Small wire or toothpick (for cleaning)
- Garden spade
Supplies Needed
- Replacement nozzles (if needed)
- Teflon tape (for loose connections)
Step-by-Step Instructions
Step 1: Identify Your Sprinkler Head Type
Determine whether you have spray heads (fixed pattern, 4-15 ft radius) or rotor heads (rotating stream, 15-50 ft radius). Spray heads have a small adjustment screw on top, while rotors have adjustment collars or screws on the side.
Step 2: Run the Zone to Observe Coverage
Turn on the irrigation zone you want to adjust and let it run for 5-10 minutes. Watch for overspray onto sidewalks, driveways, or buildings, and note any dry spots or uneven coverage patterns.
Step 3: Adjust the Arc (Spray Pattern)
For spray heads, use a flat-head screwdriver or adjustment key to turn the arc adjustment screw clockwise to decrease coverage or counterclockwise to increase. For rotors, rotate the adjustment collar at the top of the head while water is running until you achieve the desired arc (typically 90°, 180°, 270°, or 360°).
Step 4: Set the Radius (Distance)
Locate the radius adjustment screw (usually marked with + and - symbols). Turn clockwise to reduce throw distance or counterclockwise to increase. Make small adjustments (1/4 turn at a time) and test between changes.
Step 5: Level the Head
If a head is tilted or sunken, dig around it carefully and adjust the riser pipe or swing joint to bring it level with the ground. Proper leveling ensures even water distribution and prevents tripping hazards.
Step 6: Clean Clogged Nozzles
If spray pattern is uneven or weak, unscrew the nozzle and rinse it under water to remove debris. Use a small wire or toothpick to clear any mineral buildup from the nozzle openings, then reinstall.
Step 7: Test and Fine-Tune
Run the zone again for a full cycle and observe the adjusted coverage. Make additional small adjustments as needed to eliminate overspray and ensure complete, even coverage of your landscape.
Common Adjustment Scenarios
Overspray onto Sidewalks/Driveways
Solution: Reduce the arc by turning the adjustment screw clockwise 1-2 full turns. If overspray persists, reduce the radius by 10-20% using the radius adjustment screw.
Dry Spots Between Heads
Solution: Increase the radius on nearby heads or adjust the arc to provide overlapping coverage. Proper head-to-head coverage (spray from one head reaches the next) is ideal.
Uneven or Streaky Pattern
Solution: Remove and clean the nozzle to clear debris. If cleaning doesn't help, the nozzle may be worn and need replacement ($2-5 each).
Head Spraying in Wrong Direction
Solution: Rotate the entire head body (not just the nozzle) to point in the correct direction. Some heads have a locking collar that must be loosened first.
Pro Tips
- Adjust while running: Make adjustments with the zone running so you can see the immediate effect of your changes.
- Small changes matter: Make 1/4-turn adjustments and test. Over-adjusting wastes time and can damage adjustment mechanisms.
- Match precipitation rates: Don't mix spray heads and rotors on the same zone—they have different precipitation rates and require different run times.
- Seasonal adjustments: Re-check coverage in spring and fall as plant growth changes and heads may shift from foot traffic or settling.
When to Call a Professional
While head adjustment is straightforward, professional help is recommended if:
- Adjustment screws are stripped or frozen from mineral buildup
- You need to add, remove, or relocate heads for better coverage
- Pressure issues prevent proper adjustment (low or high pressure)
- You want a comprehensive system audit and optimization