Diagnosis
The constant beeping on your Ninja Foodi DualZone is a programmed system alert. For this model, it almost always means a timer has reached zero in one of the two cooking zones, signaling that food is done. Less commonly, a single beep sequence can occur when the second zone's timer begins if you're using Dual Zone mode with a delayed start. The unit beeps to ensure you don't miss the completion time.
How to Fix It
To silence the alert, press the START/PAUSE button once. This acknowledges the alert and stops the beeping. Immediately check the digital display: the timer for the zone that finished (or just started) will be flashing. If both zones are in use, the display will show "ZONE 1" or "ZONE 2" next to the flashing timer to identify which one triggered the beep. You can then either remove the food from that basket or restart a new cook cycle as needed.
If That Didn't Work
If pressing START/PAUSE does not stop a continuous, non-rhythmic beep, or if an error code (like E-01, E-02, etc.) is shown, perform a hard reset. Unplug the Air Fryer from the wall outlet and wait at least 15 minutes for its internal electronics to fully power down and reset. Plug it back in. If the error beep persists upon power-up, a component may have failed. For persistent issues not resolved by the reset, contact Ninja Customer Service at 1-877-646-5288 for further troubleshooting or service options.
Heads Up
Always ensure the cooking baskets are correctly seated and fully locked into the unit before starting a cycle. A misaligned basket can sometimes prevent the unit from operating normally and may contribute to error states.