Richdel 446 PRi Controller No Zones Activate: Common Wire and Flow Stem Checks

Richdel 446 PRi: Zones Light Up but Don't Activate

A Richdel 446 PRi controller shows zone lights when selected manually, but no zones activate. Power is present. Need to check common wire, valve flow stems, and solenoid resistance.

Troubleshooting Checklist

1. Zone switches: Ensure all zone switches are ON (not OFF)
2. Common wire: Verify white common wire connected at controller and all valves
3. Flow stems: Check valve flow control stems not screwed down too far (restricting flow)
4. Electric backflow: If present, ensure it's open and solenoid measures 20-60 ohms

Solenoid Testing

Disconnect solenoid wires. Measure resistance with multimeter on ohms setting. Reading should be 20-60 ohms. Outside this range indicates faulty solenoid needing replacement.

Controller Output Test

With zone activated, measure VAC at controller terminal (common to zone). Should be 24-28VAC. If absent, controller output failed.

Richdel Legacy Note

Richdel was acquired; parts may be scarce. Consider upgrading to Rain Bird ESP-Modular or Irritrol Rain Dial for better support and features.