Control panel displays E1 and the softener does not start a regeneration cycle

Safety first: Turn off electrical power to the softener and close the main water supply before disconnecting any hoses. Depressurize the line by opening a nearby tap.

• Check inlet valve: Verify the Nobel softener's inlet isolation valve is fully open. Many installations have a small quarter‑turn ball valve on the inlet line—ensure the handle is parallel to the pipe.
• Inspect inlet hose: Follow the flexible hose from the house supply to the softener's inlet port. Look for kinks, sharp bends, or crushing behind the unit. Straighten or reposition as needed.
• Clean inlet screen: At the Nobel control valve inlet, there is typically a small mesh filter or screen. Shut off water, unscrew the inlet union, and gently pull out the screen with needle‑nose pliers. Rinse under running water and brush off sediment. Reinstall and tighten the union without overtightening.
• Check house pressure: Open a nearby cold tap fully. If flow is weak throughout the house, the issue may be with the main supply or a pressure regulator, not the softener. Contact a plumber if house pressure is low.
• Reset the control: Restore power, open the inlet valve, and press and hold the Nobel control's reset or "Regenerate" button for 5–10 seconds (refer to your specific model manual). If E1 clears and a manual regeneration starts, monitor the first few minutes for normal operation.

If E1 returns immediately after these checks, the internal flow sensor or control valve assembly may be faulty and should be inspected by a qualified technician.