If I remember correctly, Ifrit's version of napalm is actually Originium, which is the in universe ore and fuel that causes most the problems in universe, including an infection that a lot of the operators have.
So maybe to clean the thing you have to bake it to break up the stuff? Don't know.
Probably since Ifrit's flames are from Originium arts, which is the source of oripathy, you really need to clean it thoroughly if you wanna do some maintenance on that thing (disassembling, repairing, etc.)