E4 appears on the display, often during pressure cooking; unit stops heating and may release steam.

Safety first: Do not attempt to force the lid open while the cooker is under pressure. Unplug the unit and allow it to depressurize naturally or use the manual steam release according to the Steba manual.

Steps to address E4:

• 1. Release pressure safely: Once the program stops and E4 is displayed, wait until the float valve drops (if present) and the lid unlocks. Use a utensil to operate the steam release knob if manual release is required.
• 2. Clean the pressure release valve: Remove the steam release valve cap from the lid. Rinse it under warm water and use a small brush or toothpick to clear any food particles from the vent holes. Ensure the valve moves freely.
• 3. Inspect the safety valve and anti-block shield: On the underside of the lid, remove the anti-block shield (a small metal or plastic cover) if present. Clean any starch or food build-up around the safety valve and steam channels.
• 4. Check the sealing ring: Remove the silicone sealing ring from the lid. Inspect for cracks, deformation, or hardening. A damaged ring can cause unstable pressure and trigger E4. Clean the ring and the groove thoroughly and reinstall, ensuring it is evenly seated.
• 5. Lid sensor (if applicable): Some Steba models have a lid temperature sensor or microswitch. Inspect the wiring and connector under the lid or in the hinge area for damage. Ensure the lid closes fully and the switch actuates.
• 6. Test with water only: After cleaning, run a short pressure program with only water to verify that pressure builds and releases normally without E4.

Important: If E4 recurs and you notice excessive steam leakage from the lid or safety valve, discontinue use and have the pressure system inspected by an authorized service center.