Can Your HVAC System Make You Sick? What to Look For and How to Fix It
You seal up the house, crank up the air or heat, and settle in - but a few weeks later, everyone seems to have a lingering cough, dry throat, or headache that won't go away.
Sound familiar?
It might not be a bug going around. Your HVAC system - and the air it's circulating - could be contributing to how your family feels indoors.
Here's how to tell if your HVAC system is affecting your health, and what you can do about it.
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How Your HVAC System Affects Indoor Air Quality
Most forced-air HVAC systems work by recirculating the air already inside your home.
That's efficient from an energy standpoint - but it also means that whatever is in your indoor air gets circulated repeatedly through every room.
Indoor air can contain pollutants including dust mites, pet dander, pollen tracked in from outside, mold spores, VOCs from cleaning products and furniture, and airborne bacteria and viruses. When your system recirculates that air without adequate filtration, those pollutants accumulate over time - and so do their effects on respiratory health.
Symptoms That May Indicate an HVAC Air Quality Problem
If multiple people in your household experience any of the following, especially when at home, your HVAC system's air quality deserves attention:
- Persistent coughing, sneezing, or congestion that improves when you leave the house
- Dry or irritated eyes, nose, or throat
- Headaches that seem worse indoors
- Worsening allergy or asthma symptoms
- Musty or stale odors coming from vents
- Increased dust accumulation on surfaces despite regular cleaning
- Skin dryness or irritation with no other explanation
None of these symptoms are definitive proof of an HVAC problem - but patterns that correlate with time spent at home are worth investigating.
The Role of Your Air Filter
The simplest and most commonly neglected source of indoor air quality problems is a dirty air filter. When your filter becomes clogged, two things happen: the restricted airflow causes your system to work harder (raising your energy bill), and pollutants that would have been captured are now cycling freely through your home.
The EPA recommends changing standard 1-inch filters every 30-90 days. For households with pets, allergy sufferers, or high dust exposure, common in the Inland Empire, that is a safe target. Consider upgrading to a higher-MERV media filter to capture finer particles like PM2.5, which becomes particularly important during Southern California's wildfire smoke season.
Ductwork, Mold, and Hidden Contamination
Your ductwork is hidden, which means contamination inside it is easy to miss. Poorly sealed ducts can draw air from attics, crawl spaces, and wall cavities, pulling in insulation fibers, rodent debris, and mold spores. Moisture in the duct system, from a sweating supply plenum, a clogged condensate line, or an uninsulated duct in a hot attic, creates conditions where mold can grow and circulate through your living space.
Signs that your ductwork may be the problem include musty odors that appear immediately when the system starts, visible mold near supply registers, or respiratory symptoms that are worse in specific rooms served by specific ducts.
A professional duct inspection can identify and resolve these issues by sealing or replacing damaged ducts.
UV Germicidal Lights: The Next Level of Air Purification
For households dealing with persistent biological air quality issues, recurring illness, mold sensitivity, or immune-compromised family members, UV germicidal lights installed in the HVAC system offer a meaningful upgrade beyond filtration alone.
UV-C lights installed in ductwork or the air handler work by disrupting the DNA of microorganisms such as bacteria, viruses, mold spores, and volatile organic compounds (VOCs) as they pass through the system. A photocatalytic reaction converts these contaminants into harmless water vapor and carbon dioxide. Unlike air filters, UV systems work continuously without needing regular replacement, though bulbs should be replaced annually to maintain effectiveness.
Burgeson's installs whole-home UV purification systems alongside your existing HVAC equipment. Contact us at (909) 792-2222 to discuss whether UV is the right addition for your home.
What To Do Next
If you're concerned about your indoor air quality:
- Check and replace your air filter immediately
- Schedule a professional HVAC service - your technician can assess filtration, ductwork integrity, and moisture concerns
- Ask about upgrading to a higher-MERV filter or adding a UV purification system
- Consider an annual maintenance agreement to prevent issues from developing unnoticed. Don't leave your family's health up to chance.
Call Burgeson's at (909) 792-2222 or request an appointment online.
Frequently Asked Questions
Can mold grow inside my HVAC system?
Yes. Mold can grow in the evaporator coil, drain pan, air handler, and ductwork - anywhere moisture and organic material accumulate. Regular maintenance and prompt attention to condensate leaks are the best prevention.
Do UV lights in HVAC systems actually work?
Research supports the effectiveness of UV-C germicidal irradiation for inactivating airborne pathogens in HVAC systems. They are most effective when properly sized for the airflow rate and installed in the right location within the system.
How do I know if my air quality problem is coming from the HVAC system?
Common indicators include symptoms that improve when windows are open or when you're away from home for extended periods, and odors that correlate with system operation.
Contact Burgeson's
Call Burgeson's at (909) 792-2222 or request an appointment online.