Hunter ICC Controller Ground Fault with PSR-22 Pump Relay

Resolving "Faulty Ground" Errors on Hunter Controllers

A Hunter ICC controller shows "faulty ground" error when activating a PSR-22 pump start relay. The relay clicks but the error persists even with load and line wiring disconnected—only the 24V control wires (C and P/MV) connected.

Root Cause Analysis

This typically indicates inadequate grounding of the controller, relay, or pump. The controller's internal ground reference is disrupted by the relay's electromagnetic interference or a ground loop.

Systematic Fixes

1. Verify controller grounding: Ensure the controller's ground terminal connects to a proper earth ground (ground rod or metallic water pipe).
2. Check pump motor grounding: The pump frame must be solidly grounded per NEC requirements.
3. Inspect relay mounting: Mount the PSR-22 on a grounded metal surface, not plastic or wood.
4. Separate control and power wiring: Run 24V control wires in separate conduit from 120/240V pump power wires.
5. Test relay independently: If all grounding is correct, the relay itself may be defective.