How to fix AC leak and black mold myself?« Back to Previous Page

Stop using the AC immediately and turn off its circuit breaker. The black spots indicate active mold growth fueled by the constant moisture from the leak. In Dubai's high humidity, this mold can spread quickly into wall cavities.

Your first step is to address the water source. The leak is likely a clogged condensate drain line, common in older buildings where dust and biofilm accumulate. Locate the drain pipe (usually a white PVC pipe exiting near your outdoor unit) and try to clear it with a stiff wire or by pouring a mixture of warm water and distilled vinegar down the access point near the indoor unit. Never use bleach, as it can corrode the drain pan.

For the mold on the wall, wear an N95 mask and gloves. For a small area (less than one square meter), you can carefully clean non-porous surfaces with a detergent solution. However, porous materials like drywall or plaster often absorb moisture and mold roots deeply, making DIY cleaning ineffective and just spreading spores. The wall likely needs cutting out and replacing.

Given the leak has persisted for weeks and there's visible spread, the mold contamination inside the wall is probably extensive. DIY fixes often miss hidden growth. For a situation like this in an older Bur Dubai building, a professional inspection is strongly advised to assess the full extent and provide documentation for your landlord. They can use moisture meters and thermal cameras to see behind the wall without destructive probing.