Softener stuck in regeneration; water runs to drain continuously and unit does not return to service

Safety first: Immediately place the Marlo softener in bypass to stop water waste. Unplug the unit before opening the valve head.

Step-by-step checks:

• 1. Confirm cycle stage: Note which stage the display indicates (backwash, brine, rinse). This helps identify where the valve is stuck.
• 2. Attempt manual advance: Use the front panel to step through the regeneration stages. If the display advances but the valve position does not change, suspect a mechanical issue.
• 3. Inspect drive assembly: Remove the control cover and inspect the Marlo drive motor and cam. Look for broken gears, loose set screws, or obstructions.
• 4. Check rotor movement: With power off, manually rotate the cam (if possible) to see if the rotor can move through positions. Binding indicates worn or swollen seals.

When to replace parts: Replace the Marlo drive motor if it does not run under power. Replace the rotor and seal pack kit if mechanical binding is present. If mechanics are good but the board will not advance the cycle, replace the Marlo control board.