E09 displayed and water remains hard even after recent regeneration.

Safety: Shut off water and depressurize the system before opening the mineral tank or valve head.

Steps:

• Verify settings: Check the programmed water hardness and capacity on the AquaClean control. Correct any obvious errors.
• Check salt supply: Ensure the brine tank has adequate salt and that a salt bridge is not preventing brine formation.
• Test water hardness: Use a hardness test kit on water before and after the softener. If both are similar, the resin is likely exhausted or damaged.
• Inspect resin (if accessible): Remove the valve head and visually inspect the top of the resin bed. Look for fouling with iron or sludge.
• Resin cleaning: Run a resin cleaner (approved for AquaClean systems) through the softener following product instructions.

If hardness remains high and E09 persists, the AquaClean resin bed or resin level sensor (if present) may need replacement. This is a more advanced repair often best handled by a technician.