Hey all, I have a yihua 852d+with a bad air pump control pot. I tried replacing it with another 500ohm pot, it works, but it smokes, and gets hot. Obviously it's not rated for the amperage the fan control is pushing. Unfortunately I misplaced the original pot, but it didn't have a part number on it anyway, so it wasn't useful. Does anybody know what the direct replacement is? Better yet, has anybody replaced it with one that has a switch?