Spring sprinkler start-up

Start up your sprinkler system safely in spring and check for winter damage.

Why it matters#

Proper start-up prevents water hammer damage and lets you catch freeze damage early. A thorough inspection ensures efficient watering all season.

What you'll need#

Tools#

Flathead screwdriver
Sprinkler head adjustment tool
Flashlight

Materials#

Replacement heads (if needed)
Teflon tape (if reconnecting backflow preventer)

Steps#

1. Wait for freezing weather to pass#

Don't start up until nighttime temperatures are consistently above 32°F.

2. Inspect the backflow preventer#

Check for visible damage, cracks, or freeze damage. The test ports should still be slightly open from winterization.

3. Close the backflow test ports#

Using a flathead screwdriver, close the test ports on the backflow preventer (turn clockwise).

4. Open the backflow valves#

Turn both ball valves on the backflow preventer to fully open (handle parallel to pipe).

5. Slowly open the main valve#

Find the main irrigation shutoff and open it VERY slowly—take a full 60 seconds to go from closed to open. This prevents water hammer.

6. Check for leaks at the backflow#

Look for water spraying or dripping from the backflow preventer. Tighten connections or replace damaged parts.

7. Walk the system while running each zone#

At your controller, run each zone manually. Walk the yard and observe each head for proper operation, spray pattern, and any broken heads or leaks.

8. Adjust misaligned heads#

Use a screwdriver or adjustment tool to correct spray patterns. Straighten tilted heads by digging around them and re-packing soil.

9. Replace broken heads#

Turn off the zone, dig around the damaged head, unscrew it, and install a matching replacement.

10. Clear clogged heads#

Remove the head, rinse the filter screen, and flush debris from the riser before reinstalling.

11. Set the controller schedule#

Program your watering schedule for the season. Water early morning (4-6 AM) for best results.

12. Schedule backflow testing#

Most areas require annual backflow preventer testing by a certified professional.

Pro tips#

The slow valve opening is critical—rushing it causes water hammer and can blow fittings
Run each zone for at least 3 minutes during inspection
Late April to mid-May is typically ideal timing (varies by region)
Keep spare heads in common sizes so repairs don't require a trip to the store

Warnings#

Opening the main valve too fast can cause water hammer that damages pipes and fittings
If you hear banging, close the valve and open more slowly
Don't skip the backflow inspection—freeze damage isn't always obvious

Call a sprinkler service if: you find significant underground leaks (soggy areas with no visible cause), the backflow preventer is damaged, you need backflow certification testing, or you have multiple broken heads and limited time. Professional start-up service typically costs $50-100.