Programming a Richdel 446PR50HZ Controller for Specific Watering Days (Sunday & Thursday Only)

The Richdel 446PR50HZ controller uses an interval-based schedule (every day, every 2nd day, every 3rd day, etc.) rather than a day-of-week calendar. Unfortunately, this model does not support selecting specific days like Sunday and Thursday directly. To comply with water restrictions that allow watering only on certain days, you have two practical options:

Option 1: Use the Closest Interval Setting

If your restriction allows watering every 3rd day, set the controller to “3rd day” and adjust the start day so the cycle falls on permitted days. This requires monitoring and occasional manual adjustment as the calendar shifts.

Option 2: Upgrade to a Day-of-Week Controller

Modern controllers (Rain Bird ESP-TM2, Hunter Pro-C, Orbit B-hyve) let you pick exact days (Sun, Thu) and offer smart features like weather adjustment. Replacement is straightforward: the existing field wiring (common + zone wires) connects directly to the new controller’s terminals.

Finding the Manual

For detailed programming steps, download the manual from a reliable source:

• Coast Water Works Controller Manuals – search for “Richdel 446” or “446PR”.

If you decide to upgrade, take a photo of the current wiring before disconnecting. Label each wire with its zone number. Most new controllers use the same 24 VAC solenoid wiring, so the swap is a 30-minute job.