AC mold smell: DIY bleach clean or call a professional?« Back to Previous Page

That damp smell and congestion are classic signs of an AC system hosting microbial growth, and the recent humidity spike is a major catalyst. The black spots around the vent are a visible confirmation.

Using bleach spray is not recommended. It's a surface-level fix that addresses the symptom, not the source. The smell and irritation are likely coming from a contaminated evaporator coil or ductwork deep inside the unit, which you cannot reach. Bleach can also corrode sensitive AC components and its fumes are hazardous to inhale in an enclosed space.

For a localized spot on a dry wall around the vent, a solution of distilled white vinegar can suppress it, but this won't solve the core problem. Given your symptoms are worsening and the mold is visible, a professional inspection is strongly advised. Dubai's constant AC use creates perpetual condensation inside units, providing the perfect damp environment for mold to thrive year-round.

A proper inspection uses borescopes to visually confirm growth on the coil and inside ducts, and air or swab samples sent to a microbiology lab can identify the species. This is critical, as some types common in HVAC systems here can cause more significant irritation. The report will detail the contamination level and the precise scope of remediation needed, which is essential for any company you hire to properly solve the issue.