E11 error; unit may heat briefly then shut off, or fan runs without heat.

Safety first: Unplug the air fryer and allow it to cool.

Steps:

• 1. Identify second sensor: Some Klarstein models use a second NTC sensor near the air outlet or in the cavity wall. Open the housing and trace any additional two-wire sensor harnesses from the control board.
• 2. Check mounting: Ensure the sensor is properly clipped or screwed into its metal bracket and not hanging loose. Reattach securely if dislodged.
• 3. Inspect wiring: Look for pinched, cut, or melted wires along the sensor harness. Repair or replace damaged sections.
• 4. Test resistance: Disconnect the sensor and measure resistance at room temperature. Compare to the main NTC sensor; they should be similar. An open or near-zero reading indicates a faulty sensor.
• 5. Replace sensor: Install a compatible Klarstein auxiliary NTC sensor assembly. Route the harness along the original path and secure it away from the heater and fan blades.
• 6. Reassemble and test: Refit covers, plug in, and run a test cycle. Confirm that E11 is cleared and that the unit heats and cycles normally.

Warning: Do not interchange sensors of different specifications; use the correct replacement for your model.