I have a house that's about 5 years old and had the front yard landscaping with 3 zones using Brand H control valves.
I added another 3 for the backyard running from the same control box using the wiring and water line that was left for it from when the home was installed. The backyard valves are only about 6 feet away from the front yard valves and uses the same ground wire.
Sometime over the last week, all 3 front yard valves failed. I can't even get them to turn on using the manual control on top of the valve. There seems to be some water trickling through but not much. There relief valve has pressure when I open it.
It doesn't seem to be an electrical problem since the back yard ones work fine. The house water pressure also seems as strong as normal.
Any ideas for what else I can check before I start cutting up the PVC pipe and replacing the valves?