I just fixed my air fryer. Well, not quite as I still have to wait for a replacement part, but it is back in use.
Last night, while being used the air fryer just quit. Poof! The light went out. Told my wife it looked like the internal thermal fuse gave up the ghost.
Today, it took me 1/2 hour to figure out how to take the thing apart. In hindsight, it should have been obvious by inspection how the thing was put together, but I was a bit slow today.
Found the thermal fuse immediately. Yep, it has opened up, as measured with an ohmmeter. I cut out the fuse to bypass it temporarily. Put the thing back together, and it was working again.
Now, this type of safety thermal fuse often fails on its own, but it was also possible that the fryer was overheating somehow. To test that the temperature control of the fryer still worked, I set the temperature to the lowest level at 180F, and verified that the fryer turned the heater off when the temperature was reached. Raised the setting to 250F, and verified that the heater was turned back on, then off again later. So, it was most likely that the thermal fuse failed by itself, as these often do.
Now, to order a new one, I looked at the marking on the fuse. What the heck is this "172C"? That's only 342F. The fryer's setting goes up to 400F, which is 204C. Could it be that the manufacturer allowed for the location of the fuse?
I ordered 180C parts. Cost was $7 for 5 pieces, shipped from NY by first-class mail. Or $6 for 10 from Hong Kong. I chose NY.
This common "bullet" thermal fuse looks like this (image from Amazon).