Small cooking appliances
In this page we cover air fryers, halogen ovens and related multi-function cookers.
Air fryers, halogen ovens and multi-function cooking appliances are essentially simple devices comprising some combination of electric heater, stirrer, fan and timer or programmer, and there may be one or more safety interlocks and thermal cut-outs. It shouldn't be hard to determine which is broken and hence get a head start in repairing it.
- As with all mains electrical devices, dangerous voltages may be exposed when opened and some parts may remain hot for a while after switching off. Always unplug and allow to cool down before starting work.
None of the components in this class of device is complicated except the electronic timer. The first step is always to assess what is working (if anything) and what isn't. This should give valuable clues as to where the fault lies.
Disassembly can sometimes be challenging. Search online for disassembly or repair guides or videos. Even if you can't find one for the exact model you have in front of you, guides for other models by the same manufacturer are likely to give you a few clues.
If the device is showing no signs of life, the first thing to check is the fuse in the plug. This will not often be the fault but it's so easy to check and if necessary replace that it's well worth eliminating from the outset.
Check for grease or other cooking residues which may be clogging up a fan, stirrer or other mechanical parts such as a safety interlock, or could be preventing a switch or electrical contact from working. Check for corrosion of any accessible electrical contacts, which might have been caused by steam getting to where it shouldn't.
There may be a thermal fuse to cut off the current in the event of overheating. Test it with a multimeter on a resistance range (it should record practically zero resistance). This, you may be able to replace, but make sure the replacement is rated at the same temperature and current. It may be wire-ended and simply placed in an area which is not meant to get too hot, or it may be mounted so as to be in good thermal contact with some metal part, and a replacement must be similarly mounted.
Check the heating element with a multimeter. You should expect a value in the tens of ohms, depending on the wattage, though the actual measured value with the element cold may be significantly less. On some devices the heating element might have several connections to give different heat levels, but probably more often there be just two connections to the element and the power will be controlled electronically.
A faulty electronic timer or programmer can be challenging to fix unless the fault is obvious. There will be some kind of power supply, quite likely integrated into the timer, to drop the AC mains voltage to a much lower DC voltage for the electronics. Check for swollen or leaking electrolytic capacitors or any other components showing signs of overheating or charring. Rectifier diodes can be tested with a multimeter.
If you are having trouble locating the fault, it will be worth spending a few minutes tracing out the circuit diagram. This will make it easier to understand what possible faults could cause the observed malfunction.
The heating element in these is enclosed in a quartz glass tube and may only last a couple of years of regular use before failing. Fortunately, relacements are available at reasonable cost, and can be fitted fairly easily. As with quartz halogen light bulbs, you should take care not to touch the glass with your fingers as finger grease can damage the tube when it's hot.
These simply consist of a heating element, a fan, a timer or programmer and a basket or tray for the food. There may be a paddle to stir or agitate the food.
Mechanical problems can arise, for example the paddle can get stuck, the tray or basket can get bent if dropped, and the plastic of the case or buttons can melt if they come into contact with a hot tray.
All the points under the General heading above also apply.
Numerous multi-function cookers are now available, combining a variety of functions in addition to air-frying, such as steaming, pressure cooking and rice boiling. Each function can be expected to work in the same way as a single function cooker, and might be expected to present similar faults.