Richdel 446PRi Controller Replacement: Avoid Overpriced Quotes

A 16-year-old Richdel 446PRi that suddenly stops firing zones—despite a working display—likely has failed output drivers. One contractor quoted $415 for controller + $215 for rain sensor. You can do far better for ~$150 DIY.

Diagnosis Confirmation

• Display works, programs run, countdown visible
• No zones activate (manual or auto)
• 24 VAC at transformer confirmed
• Field wiring continuity verified
• Conclusion: Controller output stage failed

Fair-Priced Replacement Options

• Irritrol Rain Dial-R (6-zone indoor): ~$110. Direct functional equivalent, same terminal layout.
• Hunter XC-600i: ~$60. More features, seasonal adjust.
• Rain Bird ESP-TM2: ~$70. Simple, reliable.

Rain sensor: Optional. Many modern controllers have seasonal adjust that reduces watering in cool/humid conditions. Add a wired rain sensor later ($25–$40) if desired.

DIY Replacement Steps

1. Turn off breaker for controller circuit.
2. Label every wire on terminal strip: C, 1–6, MV, PS, 24 VAC (yellow), 120 VAC (black/white/green).
3. Photograph terminal strip.
4. Remove old controller; mount new one.
5. Connect wires to matching terminals.
6. Restore power, install 9 V battery.
7. Reprogram schedule; test each zone.

Why the Contractor's Price Is Inflated

• Controller markup: $150 unit → $415 installed
• Rain sensor: $30 part → $215 installed
• Labor: 1 hour max for controller swap
• No license/specialty required for low-voltage irrigation wiring

You have the skills. Save $400+ and get a better controller.