Display shows E3 and unit stops heating; may occur shortly after startup

Safety first: Turn OFF electrical power and close water supply. Allow the heater to cool completely before servicing.

Steps:

• 1. Check water flow: Open a hot water tap fully. If flow is weak, clean inlet filter screens and ensure all isolation valves are fully open.
• 2. Inspect for scale: If you have hard water and the unit has not been descaled, mineral buildup may be restricting flow. Follow Electrolux instructions to flush the heat exchanger with a descaling solution using service valves and a pump.
• 3. Locate overheat thermostat / thermal cut-out: Usually mounted on the heat exchanger body. Check for manual reset buttons (some models have a small red reset). Press gently to reset if tripped.
• 4. Test continuity: With power OFF, disconnect the thermostat or thermal fuse and check continuity with a multimeter. Replace if open and not resettable.
• 5. Verify flow sensor operation: Inspect the flow sensor/turbine assembly for debris. Clean or replace if the turbine is stuck or damaged.
• 6. After corrections: Restore power and test. Monitor temperature to ensure it is stable and within normal range.

Note: Repeated E3 errors after descaling and thermostat replacement may indicate a control board or sensor calibration issue; contact Electrolux service.