Safety first: Unplug and allow the unit to cool completely before opening. Heating components can retain heat.

Check settings: Verify that a temperature above ambient is selected and that preheat time is sufficient.
Listen for relay click: When starting a cycle, listen for a click from the control board area. No click may indicate a relay or PCB issue.
Access heater assembly: Remove the outer housing to expose the heating element and thermal fuse.
Test thermal fuse and thermostat: Use a multimeter to check continuity through the thermal fuse and any series thermostat. Replace any open components with identical ratings.
Test heating element: Measure resistance across the element; an open reading indicates a failed element that must be replaced.
Inspect wiring and connectors: Tighten or replace any loose or burnt spade connectors on the heater and PCB.
PCB relay: If the heater and safety devices are good, but the relay does not energize, replace the main control PCB.

Air fryer turns on and fan runs, but there is no heat; food remains uncooked.

Possible Causes