Display shows 'H0' or similar hardness error; water remains hard

Safety: No internal electrical work is required for programming.

• Verify hardness: Test your raw water hardness using a test kit or local water report.
• Reprogram hardness: Enter the correct hardness value into the WaterBoss control following the user manual. Include iron compensation if recommended (e.g., add 5 gpg for each 1 ppm of iron).
• Save settings: Confirm that the display retains the new hardness value after exiting the menu and after a brief power interruption.
• If hardness cannot be changed: The control board may have an input or memory fault and should be replaced.