Short answer: that sticky film in your air fryer is grease that has hardened in the hot air. Scrubbing does nothing about it, soaking does.
Short answer
Drawer out, boiling soapy water in, wait ten minutes.
Take the drawer and the rack out of the machine. Fill it with boiling water and a squirt of washing-up liquid, to about two centimetres above the bottom. Leave it to stand for ten to twenty minutes. The grease lets go by itself and you wipe it away with a soft cloth.
Why scrubbing does not work
You are not dealing with grease, but with something that used to be grease.
An air fryer works with hot air that is blown around inside. That releases tiny droplets of grease, which land on the rack, against the walls and against the heating element. On those hot surfaces the grease changes: the molecules link up and form a hard, sticky layer. That is called polymerisation.
Washing-up liquid is made to bind loose grease. It does very little to that hardened layer for as long as the layer is cold and dry. Warm water changes that: the heat softens the layer again, and then the washing-up liquid gets hold of it after all. Which is why waiting works better here than scrubbing away at it.
Scrubbing is also exactly what you do not want to be doing. Underneath that layer sits a non-stick coating, and it is thinner than you think.
How do you clean an air fryer?
Five steps. The only one that costs you time is step three, and you do not have to stand over it.
- Unplug it and let it cool down. Hand-warm is enough. With a scalding hot machine the soapy water spits and you can burn yourself.
- Take the drawer and the rack out. Those two come away, and only those two go into the water. The machine itself stays dry.
- Boiling water with a squirt of washing-up liquid, left to stand for ten to twenty minutes. Water to two centimetres above the bottom, so the baked-on residue is under the surface.
- Wipe it away with a soft cloth or sponge. Anything still stuck needs longer, so top it up with hot water and wait another round. Do not start scouring harder.
- Dry everything off before it goes back in. Moisture left sitting causes smells and, in time, rust marks on the contact points.
If the manual for your model says the drawer is dishwasher safe, that works too. By hand the non-stick coating simply stays good for longer, because dishwasher salt and the high temperature leave it dull.
The water trick doing the rounds, and how to do it safely
The popular version switches the machine on with water inside. Do not do that.
You come across it everywhere: water in the air fryer, a squirt of washing-up liquid with it, a few minutes on a high setting, and the grease is supposed to come off by itself. The idea is right, the execution is not.
Here is what happens when you switch it on with soapy water inside: the water starts to boil and spits upwards, towards the heating element and the fan. Those are precisely the two parts that must never get wet. Most manuals therefore say in so many words that no water may be in the machine while it is running.
The safe version gives you the same result: take the drawer out and pour boiling water into that. The heat does the work, just outside the machine. You do not need the element to get water hot, that is what a kettle is for.
The heating element, the bit nobody ever gets to
The coil sits in the top of the machine, and that is where most of the grease settles.
Turn the machine upside down or tip it over, so you are looking up at the element from below. Usually you will see a brown haze on the coil and on the plate around it.
Wipe that off with a cloth you have dampened with hot water, and nothing else. No soapy water that can run down inside, no spray, no water running in. Wring the cloth out harder than you normally would: it should only feel damp, never wet.
If a mark stays put and will not shift, leave it. A small spot on the element does no harm. Water getting into the electronics does.
The outside and the cupboard around it
Frying with hot air still means grease ends up in the air.
You only notice it when you run a hand along. The top of the machine, the cupboard underneath, the tiles behind it and the shelf above it all pick up a thin film. You do not see it, you feel it, and it holds on to dust.
That film is still fresh grease and it sits on a smooth surface. You do not need a degreaser for that. A damp microfibre cloth lifts it off, and with a dry cloth straight after, nothing is left behind. Work from the top down, otherwise you drag it onto spots that were already clean.
Everything for this job is together under kitchen cleaning.
Where a cloth cannot reach
The grout behind your worktop and the filter of your extractor hood.
On smooth materials a cloth beats almost anything. But grease that has settled into the grout between your tiles or into the metal filter of the extractor hood is in it rather than on it. Rubbing will not get you there.
Heat does. Steam at around a hundred degrees softens hardened grease again, after which it lets go and you simply wipe it away. No degreaser, no gloves, just tap water that has been made hot enough.
What you are better off not doing
Most of the damage done to an air fryer happens during cleaning.
Wire wool, scouring pads and metal brushes. They take the baked-on residue off and the non-stick coating with it. After that everything sticks even faster.
Oven cleaner. Far too aggressive for a non-stick coating, and you do not want the traces of it in something you heat food in.
The machine under the tap. The housing with the element and the fan never goes into water and never into the dishwasher.
Baking parchment that is too big. Loose paper that is not held down by the food can blow up against the element. Only use it with something on top to keep it in place, and never while preheating.
Vinegar against the grease. Vinegar is an acid and works well on limescale. Grease asks for the opposite. Use them both, just for different problems.
How to keep it clean for longer
The difference is in when you do it, not in how hard you polish.
Wipe the drawer out while it is still hand-warm. Grease that has not cooled down yet comes away with a sheet of kitchen roll. That same grease costs you ten minutes of soaking a week later.
Unclip the rack when you rinse it out. Most of it collects under the rack, and that is exactly where nobody looks.
Cook fatty food on a lower setting. The hotter the air, the faster the grease hardens on the walls.
Frequently asked questions
Can there be water in the air fryer while it is running?
No. The water starts to boil and spits up against the heating element and the fan, and those must not get wet. The safe version is to take the drawer out and pour boiling water into that. Same result, outside the machine.
Is the drawer dishwasher safe?
Only if the manual for your model says so. If it is allowed, then go ahead, but by hand the non-stick coating stays good for longer. Dishwasher salt and the high temperature leave the coating dull and porous.
Why does it fizz when I mix soda crystals and vinegar?
Because the two of them cancel each other out. What is left is mostly water, a little salt and carbon dioxide that fizzes away. The very two things you needed are then gone. It looks powerful and it is the opposite.
What is the difference between soda crystals and bicarbonate of soda?
Two different substances. Soda crystals, or washing soda, are sodium carbonate and the fierce one of the two, which is why grease breaks down fast. Bicarbonate of soda is sodium bicarbonate, also sold as baking soda, and it is a good deal milder. In an air fryer with a non-stick coating, hot soapy water is usually enough and you need neither of them.
My air fryer smells, even when it looks clean. Why is that?
The smell is usually in the grease on the heating element, not in the drawer. That burns again every time you use it and that is what you can smell. Tip the machine over and wipe the element with a damp cloth. If it still smells after that, run it empty once with the window open.
How often should I clean it?
Give the drawer a quick wipe after every use, while it is hand-warm. The rack and the element roughly every ten uses, or sooner if you have cooked something fatty. Waiting until it turns sticky costs you more time than keeping on top of it.
Can I still get the residue off if it has been there for months?
Usually yes, but not in one go. Repeat the soak two or three times with fresh boiling water rather than scouring harder once. If it has been there for years, there is a real chance the non-stick coating underneath is worn out anyway.
More in the kitchen
Is there a pan with a burnt-on bottom standing there too? It is almost never ruined: this is how you get a burnt pan clean again. And the classic deep fat fryer full of oil calls for a different approach: how to clean a deep fat fryer.