Display shows “No Flow” even when water is being used in the home, or unit never regenerates on demand.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power and close the inlet valve before removing any plumbing connections.
Verify plumbing and bypass:
- Ensure the AO Smith bypass valve is in the Service position, not bypass.
- Confirm inlet and outlet are not reversed; check the markings on the valve body.
Inspect the turbine/flow meter:
- Remove the top cover and locate the turbine assembly on the outlet side of the valve.
- Shut off water and relieve pressure, then remove the turbine housing cap.
- Pull out the turbine wheel and inspect for debris or damage. Clean thoroughly and ensure it spins freely.
- Check the sensor and wiring for damage; reseat the connector at the control board.
Restore water and power, then run water at a faucet while watching the display. If flow still does not register, replace the turbine/flow sensor assembly.
Repair Difficulty
Required Part
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