Display shows E4; ice maker stops; water fills but ice does not harvest correctly; unit may beep.

Safety: Disconnect power and close the water supply valve before working inside the ice-making compartment.

Steps to address E4:

• Clean the ice thickness probe: Locate the metal or plastic probe that senses ice thickness at the evaporator plate. Using warm water and a soft cloth or nylon brush, remove any lime scale, slime, or debris. Do not use sharp tools that can scratch the probe.
• Clean water level sensor: If your Vestfrost model uses a water level sensor in the reservoir, drain the reservoir and clean the sensor and float assembly with a mild descaler approved for ice machines. Rinse thoroughly.
• Check sensor alignment: For optical sensors, ensure the emitter and receiver windows are clean and properly aligned. Wipe with a soft, lint-free cloth.
• Inspect wiring: Follow the sensor harness back to the control board. Look for kinks, cuts, or loose connectors. Reseat all plugs.
• Test operation: Restore power and water, then run a test cycle. Observe whether the ice thickness is now correct and whether E4 clears.
• Replace faulty sensor: If cleaning does not help and E4 persists, replace the ice thickness sensor assembly or water level sensor as specified for your Vestfrost model.

Warning: Do not use strong acids or household vinegar inside the machine unless the Vestfrost manual explicitly allows it; use commercial ice machine descaler instead.