Your Air Conditioner: Preventing And Dealing With Mold Growth In The Drip Pan

As the name implies, an air conditioner does more than cool air, it conditions air. Part of that conditioning function is removing humidity. Particularly on a humid southeast Texas summer day, your air conditioner extracts gallons and gallons of water vapor. This condensate flows into the drip pan under the air handler, then down a drain line. But that wet drip pan, located in the dark, hot surroundings of an attic or air handler closet, is a perfect environment for mold and algae.

And that’s a problem, because the growth of these fungi can clog the drain lines. As the system continues producing condensate water, the drip pan may overflow for some time before you're aware of it, causing major water damage to your home. Also, a breeding ground of mold in proximity to your system's airflow can spread unhealthy airborne mold spores by the millions into your A/C ducts and throughout your entire house.

Here are some ways to prevent and treat mold growth in the air conditioner:

  1. Keep your household environment as clean and dust-free as possible. Organic airborne particulates sucked into the HVAC system may wind up in the drip pan and provide food — the only other ingredient mold needs to thrive in addition to warmth and moisture — for mold spores.
  2. Change the A/C filter every month during the peak of cooling season. Filters full of organic material and mold spores become natural sources that feed growth in the drain pan.
  3. Schedule an annual inspection with an HVAC contractor. The technician will visually inspect the drip pan for evidence of mold or algae and verify that both the primary and backup drain lines are open and running. The technician will also disinfect the drip pan and treat it with a time-release biocide that remains active for months. Since mold in the drip pan often means a mold-contaminated evaporator coil, too, the technician will also inspect the coil and clean it with chemicals designed to destroy mold.

Conroe Air Conditioning, Heating & Refrigeration has served Montgomery County and surrounding area homeowners since 1980. We're the largest full-service HVAC contractor in the area and we're ready to show you how we've built our track record. Contact us today with any air conditioner concerns you may have.