Bella digital air fryer will not start and displays error code E1 on the control panel.

Safety first: Unplug the air fryer and let it cool completely before opening anything. Never work on the unit while it is connected to power.

Step-by-step checks:

• Power cycle the unit: Unplug for 5 minutes, then plug back in and try again. Sometimes E1 is a transient sensor read error.
• Inspect the sensor wiring: Remove the basket and look into the cooking cavity. On most Bella digital air fryers, the temperature sensor (NTC) is a small metal probe or button clipped near the heating element shroud. From the back or top cover (after removing screws), trace the two thin wires from this sensor to the main control board. Check for burnt, pinched, or broken wires and loose push-on connectors.
• Reseat connectors: Gently unplug and replug the small 2‑wire connector for the NTC on the control PCB. Ensure it is fully seated and not corroded.
• Check for obvious damage: If the sensor body is cracked, melted, or detached from its clip on the heater bracket, it will need replacement.
• Test if you have tools: With the unit unplugged, use a multimeter set to resistance (ohms) across the two NTC leads. A typical NTC will show a resistance in the 50k–200kΩ range at room temperature (exact value varies by model). If it reads open (OL) or dead short (0Ω), the sensor is faulty.
• When to replace parts: If wiring and connectors look good but E1 persists, replace the temperature sensor (NTC thermistor). If a new sensor does not clear the error, the main control PCB temperature input circuit is likely damaged and the board should be replaced.

Do not bypass the sensor (for example by shorting the wires). This disables temperature control and is a fire and burn hazard.