Air fryers are simple appliances with a small number of recurring complaints, nearly all of which trace back to loading, cleaning or expectations rather than to a fault. Working out which category a problem falls into takes a few minutes.
This guide covers the common issues on these units and the maintenance that prevents most of them.
Clearances, permitted accessories and cleaning methods differ by unit, and the DeLonghi manuals document each model in their range individually.
Smoke during cooking
The most alarming symptom and usually the most benign. An air fryer circulates hot air over food at speed, and anything that drips into the drawer beneath meets a hot surface.
Causes in order of likelihood:
Fat rendering from the food and pooling in the base. Adding a little water to the drawer beneath the basket stops it reaching smoke point and is the standard fix for fatty foods.
Residue from previous cooking burning off. This is a cleaning issue rather than a cooking one.
Light ingredients being blown into the heating element – loose herbs, breadcrumbs, baking paper not weighted down.
Overfilling, which prevents air circulating and leaves food sitting in its own fat.
Smoke accompanied by a burning smell in a clean, empty unit is a different matter and warrants stopping use.
Uneven cooking
Air fryers cook by moving hot air around food. Anything obstructing that movement produces uneven results.
Fill the basket no more than about two-thirds. A single layer gives the best results.
Shake or turn food partway through. Most recipes assume this and many people skip it.
Preheat where the model supports it – starting cold changes timings substantially.
Cut pieces to a consistent size, since mixed sizes cook at different rates by definition.
Timings and temperatures
Conventional oven recipes do not transfer directly. As a general starting point, reduce the temperature somewhat and shorten the time, then check early and adjust. Air fryers run hotter at the food surface than the set temperature implies because of the airflow.
Model capacity matters too. A recipe written for a larger basket will overcrowd a smaller one, and overcrowding is the main cause of disappointing results.
Cleaning, which prevents most problems
Clean the basket and drawer after every use. Residue left to carbonise is the source of both smoke and odour.
Check the heating element above the basket periodically. Food debris accumulates there and burns on. Clean it only when the unit is unplugged and completely cool.
Avoid metal utensils and abrasive pads on non-stick surfaces – scratched coating degrades quickly and cannot be repaired.
Confirm whether your basket is dishwasher safe before putting it in. This varies by model and repeated dishwasher cycles shorten coating life even where permitted.
Dry everything fully before reassembly.
Basket coatings and replacement parts also vary between makers, so free user manuals are the quickest way to confirm what fits.
The unit stops mid-cook
Most units have a safety cut-out that stops heating when the basket is removed, which is normal and resumes on reinsertion. A unit stopping without the basket being moved suggests something else:
Thermal protection triggering from blocked air vents. Ensure clearance around and above the unit.
A timer reaching zero, which is easy to misread on some displays.
A basket not fully seated, which the switch reads as removed.
Noise
A loud fan is normal – these units move a lot of air. A rattle usually means the basket is not seated, or something light is being blown around inside. A grinding or scraping noise is not normal and warrants stopping.
Frequently asked questions
Can I use foil or baking paper?
Usually yes, with conditions: weighted down by food so it cannot blow into the element, not covering air holes, and not touching the element. Check what the documentation for your model permits.
Why does my food come out dry?
Usually overcooking. Air fryers work faster than expected, and a light coating of oil on the food surface helps considerably.
Is the non-stick coating safe if scratched?
A visibly damaged coating should be replaced rather than used. Replacement baskets are available for many models.
Note: clearances, cleaning methods and permitted accessories differ by model. Always unplug and allow the unit to cool fully before cleaning anything above the basket.
