Display shows “H0” or similar hardness error and regeneration frequency seems incorrect.

Safety first: You can adjust programming with power on; do not open the control head while energized unless necessary.

• Verify programmed hardness: Enter the programming menu and check the hardness value. Set it to the actual incoming hardness (from a test or water report).
• Check hardness sensor (if installed): Some advanced Hellenbrand systems use an external hardness probe. Inspect its wiring and clean the probe according to the manual.
• Reset programming: If the display shows an impossible hardness or H0, perform a factory reset and re-enter all parameters.
• Monitor operation: After correction, observe the remaining capacity and regeneration intervals over several days to ensure they match expected usage.
• Replace board if needed: If hardness values continue to reset or show errors, the control board may be defective.