I have a Pentair IC20 and it too is seeing its second year opening, it ran about 1/2 of last summer. When the temp got to 72 it was turned on and out came a large white cloud out of the returns, it lasted for about 20-30 minutes and finally disapated in a few hours... everything has been normal since. Could it be that when the SWG sits dry all winter it develops some sort of coating and when reintroduced to salt water it has some sort of reaction??? I assume this is normal since more people have had the same thing happen.