How do I know if my indoor air quality is bad?

Common signs include allergy symptoms that worsen indoors, excessive dust buildup, musty odors, condensation on windows, and family members with unexplained headaches or fatigue. If symptoms improve when you leave the house and return when you come back, your indoor air quality is likely the culprit.

What MERV rating filter should I use in San Antonio?

For most San Antonio homes, a MERV 11 filter is the best balance between air quality and system performance. It captures 85-95% of particles including pollen, dust, pet dander, and mold spores. Don't go higher than MERV 13 without confirming your system can handle the airflow restriction.

Do UV lights in HVAC systems really work?

Yes. UV-C germicidal lights destroy up to 99.9% of mold, bacteria, and viruses on the evaporator coil and in the air passing through. They're especially effective in humid climates like San Antonio where mold growth on the coil is common. They require only an annual bulb replacement.

What should indoor humidity be in San Antonio?

The EPA recommends 30-50% indoor humidity. San Antonio's outdoor humidity often exceeds 70%, which makes indoor control essential. Your AC removes some humidity while cooling, but many homes benefit from a whole-home dehumidifier to stay in the safe range and prevent mold growth.

Is a whole-home air purifier worth it?

If you're running multiple portable purifiers or dealing with persistent allergies, a whole-home purifier is more effective and cheaper to operate long-term. It cleans all the air moving through your HVAC system, covering every room in the house. Combined with a good filter and UV lights, it provides the most complete air quality solution.

Is Your Home Making You Sick? A San Antonio Guide to Indoor Air Quality

You keep your house clean. You vacuum, dust, and wipe down the counters. But the air you're breathing? That's a different story. The EPA says indoor air is typically 2 to 5 times more polluted than outdoor air. In San Antonio, where humidity runs high and cedar pollen is practically a season of its own, indoor air quality deserves your attention.

What Makes Indoor Air Quality Bad?

Your home traps pollutants. Modern houses are built tight for energy efficiency, which is great for your electric bill but bad for air circulation. Common indoor pollutants include dust mites, pet dander, mold spores, pollen, volatile organic compounds (VOCs) from cleaning products and furniture, and cooking fumes. In South Texas, humidity makes everything worse by creating the perfect environment for mold and dust mites to thrive.

Signs Your Home Has an Air Quality Problem

•Allergy symptoms that get worse when you're inside (sneezing, congestion, itchy eyes)
•Dust builds up quickly, even right after cleaning
•Musty or stale smells that won't go away
•Condensation on windows or visible mold around vents and bathrooms
•Family members with unexplained headaches, fatigue, or respiratory issues
•Pet odors that linger no matter what you try

If you're nodding along to more than one of these, your HVAC system is part of the solution.

San Antonio's Humidity Problem

San Antonio's average humidity sits between 60-80% for most of the year. The EPA recommends keeping indoor humidity between 30-50%. When indoor humidity creeps above 50%, dust mites multiply, mold starts growing on surfaces you can't see (inside ductwork, behind walls), and bacteria thrive. Your AC removes some humidity as it cools, but in our climate, it's often not enough.

A whole-home dehumidifier works alongside your HVAC system to keep humidity in the sweet spot. It's one of the most effective upgrades for San Antonio homes, especially if you have a two-story house where the upstairs always feels stuffy.

Air Filters: Your First Line of Defense

Your HVAC filter does more than protect the equipment. It's the main thing standing between airborne junk and your lungs. But not all filters are equal.

•MERV 4 (basic fiberglass): Catches large dust particles. That's about it.
•MERV 8 (pleated): Catches dust, pollen, and mold spores. Good baseline for most homes.
•MERV 11-13 (high efficiency): Captures 85-95% of particles including pet dander, fine dust, and bacteria. Best choice for allergy sufferers.
•HEPA (MERV 17+): Hospital-grade filtration. Too restrictive for most residential HVAC systems without modification.

Don't just buy the highest MERV rating you can find. A filter that's too restrictive for your system chokes airflow, makes your AC work harder, and can freeze the evaporator coil. For most San Antonio homes, MERV 11 hits the sweet spot between clean air and system performance.

UV Lights: Killing What Filters Can't Catch

Filters trap particles, but they don't kill anything. Mold, bacteria, and viruses pass right through most filters or grow on the damp evaporator coil itself. UV-C germicidal lights installed inside your HVAC system destroy up to 99.9% of these biological contaminants. They shine directly on the evaporator coil where mold loves to grow, keeping it clean and your air healthier.

UV lights are low maintenance. Replace the bulb once a year, and that's it. For homes with allergy sufferers, respiratory conditions, or anyone who just wants cleaner air, they're one of the best bang-for-your-buck upgrades.

Air Purifiers: Whole-Home vs. Portable

Portable air purifiers clean one room at a time. They help, but they're not a whole-house solution. A whole-home air purifier installs directly in your ductwork and cleans every cubic foot of air that moves through your HVAC system. Some use advanced filtration, others use ionization or photocatalytic oxidation to neutralize pollutants, odors, and VOCs.

If you're running three or four portable purifiers around the house, a single whole-home unit is more effective and costs less to operate long-term.

Cedar Fever and Seasonal Allergies

If you've lived in San Antonio long enough, you know about cedar fever. Mountain cedar pollen hits hard from December through February, and it gets inside your home every time you open a door. Ragweed, oak, and grass pollen keep things going the rest of the year.

A MERV 11+ filter catches most pollen before it circulates through your home. Combine that with keeping windows closed during high pollen days and running your fan on "auto" so air passes through the filter regularly. For severe allergy sufferers, adding UV lights and a whole-home purifier can make a real difference in daily comfort.

Simple Steps to Improve Your Air Quality Today

•Upgrade to a MERV 8-11 filter and change it every 30-60 days.
•Keep indoor humidity between 30-50%. Use your AC and consider a dehumidifier.
•Run your HVAC fan on "auto" so air filters regularly throughout the day.
•Vacuum with a HEPA-filter vacuum at least once a week.
•Keep windows closed during high pollen counts and on high humidity days.
•Have your ductwork inspected. Dirty ducts circulate dust, mold, and debris every time the system runs.
•Don't block return air vents with furniture. Your system needs airflow to filter properly.

When to Call a Pro

If you're dealing with persistent mold, unexplained health symptoms, or humidity you can't control, it's time for a professional IAQ assessment. We'll test your air, inspect your ductwork, and recommend solutions based on what your home actually needs. Not the most expensive option. The right one.