General Assist Customer Information

Air Conditioner Smells

Common causes of mouldy, damp or unpleasant odours from an air conditioner
Unpleasant smells from an air conditioner are commonly linked to moisture, mould or mildew growth, dirty filters, or condensation that is not draining correctly. Cleaning and servicing may be required to identify and remove the source of the odour.

Mould and Mildew

One of the most common odour concerns with air conditioners is a mouldy or mildew smell. If this type of odour is present, mould or fungus may have started growing within the air conditioning system.

Air conditioners naturally remove moisture from the air while cooling. If that moisture is not draining correctly, it can remain within the system and create conditions where mould or fungus can grow. Dirty filters can also contribute to unpleasant smells.

Recommended action: Arrange for a trained HVAC technician to inspect and clean the system. A professional can properly clean the affected components and apply suitable treatments where required to remove fungal contamination and improve air quality.

Dirty or Clogged Air Conditioner

An air conditioner may sometimes produce an odour similar to feet or wet carpet. This can occur when condensation remains within the system instead of draining away correctly.

A heating and cooling professional should inspect the unit, resolve any drainage or cleanliness issues, and provide advice on the appropriate ongoing maintenance for the system.

Dirty filters can also affect operation. If filters become clogged, airflow through the air conditioner is reduced. This can cause unpleasant smells, inefficient performance and may contribute to damage or failure of important components.

What Should I Do?

1Check whether the air conditioner filters are dirty or clogged.
2If there is a mouldy, mildew, damp, wet-carpet or similar persistent smell, arrange for the system to be professionally inspected and cleaned.
3Ask the technician to check that condensate is draining correctly and that moisture is not remaining within the unit.
4Follow the technician's recommendations for cleaning and ongoing maintenance.
Important: If mould or fungal contamination is suspected, professional cleaning is recommended rather than attempting to treat internal components without the appropriate training and equipment.