[NavyB]

Hi Guys,

Anyone come across a similar staining before, it's on K-rend and though it's near air vents there is another area off camera which is not near any air vent and identically block shaped - algae or dust laden moist air? What's your recommeded treatment/chem

Cheers

[chris scott]

Send the image to K-rend and ask them for the best coarse of action. Using the wrong chemical might damage the surface…. that could leave you liable. Some  chemicals will  clean it with consequences furthur down the line.