E10 displayed and hardness remains high after regeneration

Safety: No internal electrical work is required for basic checks, but unplug the unit before opening the control housing.

• Verify programming: Enter the Aqmos programming menu and confirm that water hardness, resin volume, and salt dosage are set according to the installation manual and local water analysis.
• Check salt type and level: Use high-purity softener salt (pellets or tablets). Ensure the brine tank is at least 1/3 full and free of bridges or mush.
• Inspect brine draw: During regeneration, observe the brine level. It should drop steadily during the brine draw stage. If not, address brine suction issues (injector, brine line, brine valve).
• Perform manual regeneration: After correcting settings and salt issues, run a full manual regeneration and test water hardness at a tap after several minutes of flow.
• Consider resin condition: If hardness remains high, the resin may be exhausted or fouled (iron, manganese, organics). Resin cleaning chemicals or full resin replacement may be required.