Err10 displayed, unit regenerates too frequently or not at all despite water usage

Safety: Disconnect power before entering installer settings or opening the cabinet.

• 1. Verify programming: Check that water hardness, capacity, and reserve settings match your water test and North Star model specifications. Correct any obvious errors.
• 2. Confirm meter size: Ensure the meter/turbine size in the installer menu matches the physical valve (e.g., 3/4" or 1"). Incorrect selection can cause miscalculated usage.
• 3. Test flow sensor: With power on, run water at a faucet and watch the display for flow indication. If the usage does not increment, inspect and, if needed, replace the turbine/flow sensor assembly.
• 4. Factory reset: Perform a factory reset of the control and re-enter all settings. Monitor regeneration behavior over several days.
• 5. Replace control board: If metering remains erratic with a known-good turbine and correct settings, replace the electronic control board.