All Six Toro Valves Stuck Open After Winter: Pressure and Sequence Fix

Why All Valves Stay Open After Winterization and How to Close Them

10-year-old Toro system, 1" valves. All 6 zones stuck open after winter. Clock unplugged. Valves disassembled—no dirt, no cracks.

Physics: Valves Need Pressure to Close

Electric valves use water pressure + spring to close the diaphragm. If all valves are open simultaneously, pressure drops too low for any to close.

Recovery Procedure

1. If valves have flow control: Close flow control on all but one valve. Turn water on. The one open valve will pressurize the line, allowing others to close. Then open flow controls one by one.
2. No flow control: Shut off main water. Relieve pressure. Turn water on quickly to slam valves shut. Ensure timer is OFF.

This restores normal operation. Then investigate why they all opened (controller fault? power surge?).