E13 error; unit may shut down when high temperatures are selected or after long cooking cycles.

Safety first: Unplug the air fryer and allow it to cool completely. Grease and hot surfaces can cause burns.

Steps:

• 1. Clean thoroughly: Remove basket and pan. Clean all accessible surfaces of grease, especially around the heater guard and fan intake. Use a non-abrasive cleaner and avoid soaking electrical parts.
• 2. Check vents: Inspect rear and bottom vents for dust, grease, or obstructions. Clean with a soft brush and vacuum if necessary.
• 3. Verify fan operation: With the unit reassembled, briefly power on and listen for the fan. If it is slow, noisy, or intermittent, refer to the fan motor fault entry and repair or replace the fan motor.
• 4. Inspect high-limit thermostat: Open the housing and locate any bimetal thermostat near the heater. Ensure it is firmly attached to the metal surface. A loose thermostat can sense higher temperatures and trip early. Tighten mounting screws.
• 5. Replace thermostat if faulty: If the thermostat is cycling at too low a temperature (verified with a thermometer and test runs), replace it with the correct Klarstein high-limit thermostat.
• 6. Test at lower temperature: Reassemble and run the fryer at a moderate temperature (e.g., 160°C) for 15–20 minutes. If E13 does not appear, gradually test higher settings.

Warning: Do not cover vents or operate the fryer inside cabinets; this can cause repeated overheat errors and fire risk.