If the inside of your house smells like mold when you turn on the air conditioner but not when you use it for circulation, there could be a few reasons for this phenomenon:
Condensation in the Air Conditioner: Air conditioners remove humidity from the air as they cool it. This process creates condensation within the unit, and if the moisture isn't properly drained or if there's a buildup of mold or mildew in the unit's components, it can lead to a musty smell being emitted when the AC is turned on.
Dirty or Clogged Air Filters: Air filters in air conditioners are designed to trap dust, dirt, and other particles, including mold spores. When the filters are dirty or clogged, they can become breeding grounds for mold and mildew, which can then be circulated throughout the house when the AC is running.
Ductwork Contamination: If there's mold or mildew growth within the ductwork, turning on the air conditioner can push the spores into the living space, causing the musty smell. Ductwork can accumulate dust, debris, and moisture, creating a conducive environment for mold growth.
Moisture or Mold in the Indoor Unit: The indoor unit of the air conditioner can accumulate moisture, especially if there's a drainage issue or if the unit is not cleaned and maintained regularly. This moisture can lead to mold and mildew growth, resulting in the moldy smell when the AC is turned on.
Hidden Mold Growth: Mold can grow in hidden or less accessible areas such as behind walls, under carpets, or in the insulation. When the air conditioner is turned on, it may disturb the spores, leading to the smell being released into the air.
To address this issue, consider the following steps:
Regular Maintenance: Schedule regular maintenance for your air conditioner, including cleaning the indoor unit, checking drainage, and replacing or cleaning air filters.
Clean Ductwork: If there's a suspicion of mold growth in the ductwork, it's essential to have it professionally cleaned and inspected.
Control Indoor Humidity: Use a dehumidifier if needed to control indoor humidity levels, which can help prevent mold growth.
Inspect for Hidden Mold: If you suspect hidden mold, consider having a professional mold inspection to identify the source and take appropriate remediation measures.
Improve Ventilation: Proper ventilation helps to reduce moisture and improve air circulation, which can mitigate mold growth.
If the problem persists or if you have health concerns related to mold exposure, it's best to consult with a professional HVAC technician or mold remediation specialist to assess your home's specific situation and recommend the appropriate actions.