Solving "FUSE" Errors on Richdel 446PR Controllers

What "FUSE" Means on Zone 5

A flashing "FUSE" message when zone 5 runs indicates a short circuit in that zone's circuit—most commonly a failed solenoid.

Quick Fix: Replace the Solenoid

1. Turn off water to the zone.
2. Unscrew the solenoid (counter-clockwise) from the valve bonnet.
3. Note wire connections (polarity doesn't matter for solenoids).
4. Install the new solenoid, matching brand, model, and valve size.
5. Reconnect wires and test.

If the Error Persists

The field wire between the controller and valve may be nicked or shorted to ground. Inspect the wire path for damage (e.g., from digging, rodents, or UV degradation).

Valve Identification

Before buying a solenoid, record the valve brand (e.g., Richdel, Irritrol, Toro), model number, and size (¾", 1", etc.). Manufacturers use proprietary solenoids; they are not interchangeable.

Resource

irrigationtutorials.com has detailed solenoid replacement guides with photos.