Mold in Air Ducts: How to Detect, Remove and Prevent It
HVAC mold is more common in coastal Torrance than most homeowners realize, and the consequences for indoor air quality are serious.
How it gets started
Mold needs moisture, organic material and the right temperature. HVAC systems supply all three: condensation at the AC coil, organic dust as food, and moderate temperatures year-round.
How to detect it
Musty odor when the system runs. Visible black or greenish growth at registers. Unexplained respiratory symptoms that improve when you leave the house. Air quality testing can confirm it definitively.
Why DIY won't work
Spraying bleach into registers doesn't reach the deep contamination, and bleach itself can damage metal ductwork and contribute to other indoor air problems. Professional remediation with proper containment is the only effective approach.
What proper remediation looks like
Negative-air containment to prevent spore release. Mechanical removal of all visible growth. EPA-registered antimicrobial application. Identification of the moisture source so it doesn't recur.
Prevention
Annual coil cleaning. Properly sized AC equipment (oversized units short-cycle and don't dehumidify). Clean condensate drain lines. UV light installation at the coil for high-risk systems.