WorthFlorida
Clinical Trail 5th session completed 4/24/24.
Both valves must be open for water to flow. You may have some valves stuck in the open position. Those diaphragms can get hard or debris is in them. Perhaps a neighbor or a lawn guy came buy and noticed your sprinklers going off so he turned the valves on the preventer to save the day. Last fall I had to turn off my neighbors water meter off (a reclaimed water system here in Avalon Park, FL for irrigation) because one zones would not shut down. I never could find the bad valve but she had someone fixed the system for her.
https://www.zurn.com/products/water-safety/backflow-prevention/950xlt2
https://www.zurn.com/products/water-safety/backflow-prevention/950xlt2
