Thank you Ray for responding. I do have several open zones (24 total zones with 10 used.) I haven’t tried to disconnect one of the valves yet (no time.) I have moved the valves to different zones to try to diagnose it. It was working fine for 4 years or so. Separating the valves is easier said than done, 150 feet of wire would need to be pulled I think. I’ll take a closer look tomorrow or Tuesday (day off) and I’ll let you know.