Display shows E03 and the unit remains in service without regenerating

Safety first: Isolate the BWT Perla from the water supply and power. Depressurize the system by opening a downstream tap.

• Check for flow indication: With the unit powered, open a tap and check if the display shows water flow or consumption. If not, the flow meter is not registering any flow.
• Inspect flow meter assembly: The flow meter is typically integrated into the valve head on the inlet side. Remove the inlet union and carefully extract the turbine cartridge, following the BWT Perla service manual.
• Clean turbine: Rinse the turbine wheel under running water. Remove any sand, rust, or scale. Ensure the wheel spins freely with a gentle puff of air or by hand.
• Check wiring: Inspect the small sensor cable connecting the flow meter to the control board for damage, loose connectors, or corrosion. Reseat any loose connectors firmly.
• Reassemble and test: Reinstall the turbine in the correct flow direction (indicated by an arrow on the body). Restore water and power, then open a tap and verify that the display now registers flow and that the E03 code clears after a reset.