Air fryer overheats; exterior becomes excessively hot and food burns quickly even at low settings.

Safety first: Unplug the air fryer immediately and allow it to cool. Do not leave the unit unattended if it is overheating.

Step-by-step checks:

• Check temperature setting: Confirm you are not accidentally using a high preset. If the unit still overheats at low settings, proceed.
• Inspect sensor placement: Locate the NTC sensor near the heater. Ensure it is firmly attached to its bracket and not hanging away from the airflow, which can cause false low readings.
• Sensor test (advanced): With the unit unplugged, measure the sensor resistance at room temperature and compare to specifications if available. A very low resistance may indicate a shorted sensor.
• High-limit thermostat: Verify that the high-limit thermostat is properly mounted and not bypassed. If it has failed closed, it may not cut power when overheated.
• Control board relay: Inspect the heater relay on the main board. If contacts are welded closed, the heater may stay on continuously. Board replacement is required in that case.

When to stop: Overheating is a fire hazard. If you cannot clearly identify and correct the cause, discontinue use and seek professional service.