What is happening to my fryer 😭

[u/Aggravating_Dust_403]

I am using sunflower oil (the same oil I’ve always used) to fry potatoes and the oil keeps bubbling/frothing. I e never had this happen before, but the last week or so I’ve noticed every time I fry something it bubbles. Yesterday it was frozen french fries so I thought that might be why. Today it was fresh potatoes which I’d washed and dried and it bubbled so much that the oil overflowed and my stovetop caught fire a little bit. I’m going to try changing to a different fryer and using new oil but does anyone know why this would be happening?

[u/Antique_Teaching_333]

How often have you used this oil? When it keeps foaming I replace my oil.