Austin Asthmatics: Summer AC Fueling Fungus Growth?

By Franklin Everett Shaw

November 9, 2025

The air hangs thick and heavy, a familiar blanket in Austin summers. You step inside, seeking refuge in the cool embrace of your air conditioner, only to be met with a faint, musty odor. It’s not just unpleasant; it’s a warning sign. Mold. In Austin, where humidity reigns supreme, your AC unit can become a breeding ground for these unwelcome guests, impacting your health and your home.

Austin’s unique climate creates a perfect storm for mold growth in AC systems. The high humidity, combined with the condensation produced by cooling, provides the moisture mold needs to thrive. Dust and organic matter that accumulate in the unit serve as food. This isn’t just about a dirty filter; it’s about a potential health hazard lurking in the very air you breathe.

So, what can an Austin resident do? You don’t have to resign yourself to a moldy fate. A proactive approach, combining DIY cleaning with professional maintenance, is your best defense.

Let’s start with the DIY arsenal. Vinegar and baking soda, those humble kitchen staples, are surprisingly effective mold fighters.

Here’s a step-by-step guide to cleaning your AC unit yourself:

Safety First: Turn off the power to your AC unit at the breaker box. This is crucial to prevent electrical shock.
Disassemble: Remove the access panels to expose the evaporator coils and blower fan. Consult your AC unit’s manual for specific instructions.
Vacuum: Use a vacuum cleaner with a brush attachment to remove loose dust and debris from the coils, fan, and surrounding areas.
Vinegar Solution: Mix equal parts white vinegar and water in a spray bottle. Vinegar’s acidity kills many common mold species.
Spray and Soak: Generously spray the vinegar solution onto the evaporator coils and blower fan. Let it sit for about 15-20 minutes to allow the vinegar to penetrate and kill the mold.
Baking Soda Paste (for stubborn areas): For areas with visible mold growth, create a paste of baking soda and water. Apply the paste to the affected areas, let it sit for 30 minutes, and then scrub gently with a soft brush.
Rinse (Optional): If you used the baking soda paste, you can lightly rinse the cleaned areas with water. Be careful not to oversaturate the components.
Reassemble: Once everything is dry, reassemble the AC unit.
Run the Fan: Run the AC fan (without cooling) for an hour or two to ensure everything is completely dry.

This DIY cleaning is a great start, but it’s not a substitute for professional maintenance. Think of it as brushing your teeth – essential, but not enough to replace a dentist’s visit.

Austin’s unique environment demands specialized AC maintenance. Here’s what to look for in a local HVAC technician:

Experience with Austin Homes: Technicians familiar with Austin’s housing stock and common AC issues are better equipped to diagnose and address mold problems. Look for companies with a strong local reputation.
Mold Prevention Focus: Ask about their mold prevention strategies. Do they offer coil cleaning services with antimicrobial treatments? Do they inspect for potential moisture sources?
Duct Cleaning: Austin’s dusty conditions can lead to dirty air ducts, which can contribute to mold growth. Ask about duct cleaning services and whether they use HEPA-filtered equipment.
Proper Drainage: Ensure your AC unit’s condensate drain line is clear and functioning correctly. A clogged drain line can lead to water buildup and mold growth. Technicians should inspect and clear the drain line during routine maintenance.

Ignoring mold in your AC unit can have serious health consequences, especially for asthmatics. Common mold types found in Austin AC systems, such as Aspergillus and Cladosporium, can trigger allergic reactions, respiratory problems, and asthma attacks.

If you suspect a significant mold problem, consider professional mold testing. Several companies in Austin offer air quality testing services to identify the types and levels of mold present in your home. This information can help you determine the best course of action for remediation.

Here are some local resources for mold testing and remediation in Austin:

Mold Inspection Sciences: Offers comprehensive mold testing and inspection services.
EnviroCare: Provides mold remediation and water damage restoration services.
Austin Air Duct Cleaning: Specializes in air duct cleaning and mold removal.

Don’t wait for the musty smell to become overwhelming or for respiratory issues to develop. Take proactive steps to combat mold growth in your AC unit. Regular DIY cleaning, combined with professional maintenance from an Austin-savvy HVAC technician, can help you breathe easier and enjoy a healthier home. Remember, in Austin, fighting mold is not just about comfort; it’s about protecting your health and well-being.