How to fix AC leak and remove wall mold for good?« Back to Previous Page

The black patches are likely mould from the AC condensate leak, made worse by Dubai's high humidity. For a small patch (under one square foot), cleaning it yourself is possible. Start by fixing the leak; the drain line is most commonly blocked. Turn the AC off, locate the drain pipe (usually a white PVC pipe near the outdoor unit), and check for algae or sludge blockage. Flushing it with a mixture of warm water and vinegar can often clear it.

To clean the wall, wear an N95 mask and gloves. Scrub the mouldy area with a solution of detergent and water. Avoid bleach, as it doesn't prevent regrowth and can damage paint. Dry the area completely with a fan. For porous surfaces like drywall, if the staining is deep, the affected section may need to be cut out and replaced.

To stop it from coming back, the room must stay dry. Ensure your AC is correctly sized and running consistently to manage humidity, even when the room is unoccupied. Use a hygrometer to monitor; indoor humidity should be kept below 60%. Improve air circulation by regularly airing out the room when outdoor humidity is lower, typically early morning. Consider a standalone dehumidifier for bedrooms that persistently feel damp.

For recurring leaks, widespread mould, or if the wall feels soft, a professional inspection is advised. They can perform a pressure test on the AC drain system, assess the wall for moisture intrusion, and use lab testing to identify the mould species, which is critical for assessing risk and verifying the cleanup was successful. In Dubai villas, persistent dampness often requires a combined approach of AC servicing and environmental control.