irrigation backflow winterization

Sprinkler Backflow Blowout

  1. Close main shutoff valve (A) by turning clockwise as far as possible.
  2. VERY IMPORTANT! Remove upstream drain plug (B).
  3. Open test cocks (C) and isolation ball valves (D) to depressurize line.
  4. Purge with pressurized air.
  5. Reinstall drain plug (B).
  6. Leave test cocks (C) and isolation ball valve handles (D) in 45 deg angle to drain ball valves and prevent casting damage.