I wonder why that would be?
what is on the coils that causes the corrosion? aluminum is a pretty stout metal, it tends to hold up in places that would make steel cry. flowing water will uncover the surface plating effect in the aluminum, is there exposed tubing on a flow location? are there chinese drywall fumes in there?

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!