E15 error and unit indicates low inlet pressure or fails to start regeneration

Safety: Turn off power and close valves before removing any filters or screens.

• Measure pressure: Use a pressure gauge on a nearby tap to confirm that inlet pressure meets Aqmos minimum requirements (typically around 1.5–2 bar or as specified).
• Check inlet valve: Ensure the softener’s inlet shutoff valve is fully open.
• Inspect pre-filter: If an inline sediment or carbon filter is installed before the softener, shut off water, remove the filter cartridge, and check for clogging. Replace if dirty.
• Clean inlet screen: Remove the inlet hose and clean any mesh screen at the softener’s inlet port.
• Re-test: Restore water and power, clear the error, and attempt a manual regeneration. If E15 persists with verified adequate pressure, the pressure sensing circuit or flow sensor may be faulty.