Air fryer shows H3 and shuts off shortly after starting a cooking cycle.

Safety first: Disconnect power and let the unit cool.

Inspection steps:

• Locate the sensor: Find the NTC sensor inside the cavity near the heater. Confirm it is clipped firmly to the metal liner and not hanging or touching the heater coil.
• Check for grease buildup: Clean the sensor and surrounding area with a soft cloth and mild detergent. Avoid pulling on the sensor wires.
• Reposition sensor: If the sensor has slipped out of its bracket, carefully reposition it so it measures cavity air temperature, not direct heater temperature.

Corrective actions:

• Replace the sensor if its insulation is burnt or if it has been in direct contact with the heater.
• If H3 continues after sensor replacement and correct mounting, the main control board may be faulty.