Spring Startup Guide for Winterized Irrigation Systems

Step-by-Step: Safely Recharging Your System After Winter

Restarting a winterized system requires a careful sequence to avoid water hammer and detect freeze damage. Follow this procedure for a smooth spring startup.

Pre-Startup Checklist

• Close the winterization drain (usually a hose bib) and all backflow preventer test cocks.
• From the controller, manually activate the zone farthest from the water source.

Pressurize Slowly

1. Open the main isolation valve gradually—take 30–60 seconds to go from closed to fully open.
2. Allow the farthest zone to run until all air is purged and flow stabilizes.
3. Shut off that zone from the controller.

System Inspection

Walk the property checking for leaks, misaligned heads, and proper coverage. Then manually run each zone one by one, verifying spray patterns and adjusting as needed.

Schedule Adjustment

Reduce run times for early spring (cooler temperatures, lower ET). Gradually increase frequency and duration as summer heat arrives. A rain sensor will prevent wasteful watering after storms.