Display shows ERR6 and valve remains in backwash or brine stage indefinitely

Safety: Unplug the unit and close the inlet valve. Open a nearby faucet to relieve pressure.

• Check drain line: Inspect the drain hose from the control valve to the drain. Ensure it is not kinked, elevated too high, or blocked. Remove the hose from the drain fitting and flush it with water to clear obstructions.
• Verify water pressure: Confirm that house water pressure meets AFWFilters specifications (typically 20–100 psi). Very low pressure can prevent proper cycle completion.
• Inspect piston and seals: Remove the control valve cover and access the piston and seal/spacer stack. Look for scoring, swelling, or debris. Clean the valve body and replace the piston and seal kit if worn.
• Check drive motor operation: With the cover off and power restored, carefully observe whether the motor turns the cam during a manual regeneration. If the motor does not run or stalls, replace the drive motor.
• Retest: After clearing the drain and servicing the valve, run a full manual regeneration and confirm that each stage advances and completes without ERR6.