E3 error and display frozen, regeneration stops mid-cycle

Safety: Disconnect power and place the softener in bypass before servicing.

• 1. Locate position sensor: On many RainSoft valves, a micro-switch or optical encoder monitors cam position. It is usually mounted near the cam gear or motor shaft.
• 2. Inspect for contamination: Remove any cover over the encoder wheel. Look for iron, dust, or salt dust buildup on the wheel or sensor. Clean gently with compressed air or a soft brush.
• 3. Check switch actuation: If a micro-switch is used, manually rotate the cam (with pressure relieved) and listen/feel for the switch clicking. If it does not actuate, adjust its position or replace it.
• 4. Verify wiring: Ensure the sensor harness is fully seated on the control board and that no wires are broken at the connector strain relief.
• 5. Reset control: After cleaning and reseating, restore power and perform a control reset (per RainSoft manual). Start a manual regeneration and observe if the valve now indexes correctly.

Escalate: If E3 returns and the sensor and wiring test good, the control board may have a failed input channel and should be replaced by a qualified technician.