Richdel 445 Hybrid One Zone Low Pressure: Solenoid Port Clog

Richdel 445 Hybrid: One Zone Low Pressure Despite New Valves

21-year-old Richdel 445 with 2 new brass valves (9 heads each, 3/4" line). One zone low pressure from controller, but good pressure when manually bled at valve.

Diagnosis: Solenoid Port Clogged

New valves rule out diaphragm. Good manual pressure rules out supply line. Controller activates solenoid but valve doesn't open fully. Solenoid bleed port (tiny hole in solenoid chamber) likely clogged with debris.

Cleaning Procedure

1. Turn off water to valves
2. Unscrew solenoid from valve bonnet
3. Locate tiny hole in center of solenoid chamber
4. Clear with needle/small wire
5. With solenoid off, turn water on → should see steady stream from hole
6. Reinstall solenoid, test from controller

Why This Happens

Debris from supply line or new installation lodges in critical solenoid vent port. Valve needs this port to vent upper chamber for full opening. Manual bleed bypasses this port.