Air fryer heats but never reaches set temperature; cooking is consistently underdone and preheat takes very long.

Safety: Unplug and cool the unit before internal inspection.

Steps to improve poor heating:

• Rule out overloading: Cook a small test batch (half basket) to ensure the issue is not due to overfilling.
• Clean interior: Heavy grease on the element and fan guard can reduce effective heating. Clean the element area and fan guard thoroughly with a non-abrasive sponge once cool.
• Check heater connections: Remove the bottom cover and inspect heater terminals and wiring for looseness or discoloration. Tighten or replace burnt connectors.
• Measure element resistance: Compare the measured resistance of the heating element to the specification for your Ultrean model (often printed on the element or in service data). A significantly higher resistance than spec indicates a weak element that should be replaced.
• Sensor/board consideration: If the element is in spec, the temperature sensor may be reading too high, causing the board to limit power. Replacing the NTC temperature sensor or main control board may be required to restore accurate heating.

Tip: Use an oven thermometer placed in the basket to verify actual temperature versus set temperature.