Hardie/Richdel Controller Behavior After Power Outage

A Hardie Irrigation controller (model RICHDEL 476 PRi, 110695, 546201 Rev:D) has battery backup. The owner asks whether a reset is needed after an electrical outage and what time will display when power returns.

Battery Backup Function

If the backup battery is healthy, the controller retains its program, time, and settings during a power outage. Upon power restoration, it should display the correct current time and resume scheduled operations automatically. No manual reset is required.

When to Replace the Battery

• If the time reverts to a default (often 12:00 AM) after an outage.
• If programs are lost.
• As preventive maintenance every 1–2 years.

Check the battery compartment (usually a 9V alkaline) and replace if the controller shows signs of memory loss.