ERR 05 displayed; softener does not count down capacity or may regenerate too often or not at all.

Safety: Unplug the unit before accessing the control board. No plumbing disassembly is usually required for this error.

• Verify programming: Enter the installer setup and confirm the meter type and size match the installed Pentair meter (e.g., 3/4" turbine, 1" turbine). Correct any mismatch.
• Check wiring route: Ensure the meter cable is not routed alongside high-voltage lines or pump motor wires that can induce electrical noise. Re-route if necessary.
• Inspect connectors: Reseat the meter connector on the control board. Look for corrosion or bent pins.
• Diagnostic flow test: Use the control’s diagnostic mode to monitor flow pulses while running water. If readings jump erratically or show impossible values, suspect a bad meter or board.
• Replace components: If a known-good meter still produces ERR 05, replace the Pentair electronic control board. If swapping the meter resolves it, replace the Pentair flow meter/turbine assembly.