How do I clean A.C. stain on roof?

[jimmy77]

I've got a great big stain on both sides of the roof where the A.C. drains off the condensate. Kind of a greenish color.
jimmy77

[SteveC7010]

Originally Posted by jimmy77

I've got a great big stain on both sides of the roof where the A.C. drains off the condensate. Kind of a greenish color.
jimmy77

There are already several extensive threads on cleaning and maintaining roof membranes. Using the search function will find them for you.

The short answer is a medium bristle brush and a mild cleaning agent like borax or Dawn detergent.

[therink]

I have the same stain you refer to. I clean my roof regularly and have tried to remove the stain with no success. The stain is caused by the oxidation of the metals in the AC unit. I am not worried about it as it isn't damaging anything and it can't be seen anyway. I figure that a cleaning agent or scrubbing required to remove the stain would likely damage the membrane as the stain is imbedded.
Steve

[hankaye]

Howdy All;

Anyone try using oxy-clean or some like product???
The "green" color mentioned would indicate (to me),
a biologic thing... the stuff that the oxy-cleaners
are good at removing.

hankaye