How Your HVAC System Affects Fall Allergies

September brings cooler mornings, changing leaves and, for many people, the return of uncomfortable fall allergies. Ragweed is one of the biggest seasonal allergy triggers, especially in the eastern United States. The Asthma and Allergy Foundation of America (AAFA) reports that nearly 50 million people in the U.S. experience symptoms related to ragweed pollen and that ragweed season commonly peaks in mid-September.

Sneezing, congestion, itchy eyes, a runny nose and an irritated throat are common allergy symptoms associated with ragweed. While your HVAC system cannot prevent or treat an allergy, it can affect how pollen, dust and other airborne particles move throughout your home.

Ralph Mann & Sons has helped Connecticut homeowners with heating, cooling and indoor comfort since 1916. Understanding the connection between your HVAC system and fall allergies can help you take practical steps toward cleaner air indoors.

What Does Your HVAC System Have to Do With Fall Allergies?

Outdoor allergens do not always stay outdoors, as they can be transported inside through HVAC units or on personal items.

Pollen can enter through open doors and windows or be carried indoors on clothing, shoes, and pets, posing a challenge for allergy sufferers. The U.S. Environmental Protection Agency (EPA) lists pollen, mold, dust mites and animal dander among the biological contaminants commonly found inside homes.

Your heating and cooling system moves air throughout the house whenever it operates. As that air returns to the HVAC equipment, the filter can capture some of the particles circulating through the system.

Filtration matters because Americans spend about 90% of their time indoors, according to the EPA. The agency says HVAC filters and portable air cleaners can reduce indoor particle pollution, although no filter can remove every pollutant from a home.

That distinction is important. A good filter can be part of an indoor air quality strategy, but it should not be viewed as a complete solution by itself.

Why Can Fall Allergies Feel Worse Indoors?

Ragweed typically begins releasing pollen in August and may continue through September and October, exacerbating issues for allergy sufferers. The American College of Allergy, Asthma and Immunology notes that pollen levels in many areas are highest in early to mid-September, making this an important part of fall allergy season.

Opening the windows on a comfortable fall afternoon may bring that pollen indoors. Once inside, particles can settle on floors, furniture, and other surfaces, and later become airborne again, especially if the air ducts are not properly maintained.

High humidity can create another indoor air quality concern, such as mold spores proliferating in the environment.

The EPA recommends keeping indoor relative humidity below 60% and ideally between 30% and 50% humidity levels are often recommended for optimal indoor comfort.. Higher humidity can support mold growth, while managing moisture with a dehumidifier can also help limit other biological contaminants.

Your air conditioner naturally removes some moisture while it operates. In September, however, your air conditioner may run far less frequently than it did during July or August, which can affect humidity levels indoors.

That seasonal change can affect both humidity control and filtration. The EPA notes that central HVAC filters generally filter air only while the system is operating. In many homes, heating and cooling equipment runs less than 25% of the time during the heating and cooling seasons.

That is one reason indoor conditions can feel different during the transition from summer to fall.

Signs Your HVAC System May Need Attention

Allergy symptoms themselves do not mean there is something wrong with your HVAC system. However, certain comfort or airflow problems may be worth investigating.

Watch for weak airflow from registers, excessive dust around vents, musty odors, unusually high humidity or a filter that becomes dirty very quickly.

Moisture deserves particular attention. The Centers for Disease Control and Prevention recommends keeping indoor humidity no higher than 50% when possible to help discourage mold growth.

A musty smell, visible moisture or condensation should not simply be covered up with an air freshener. The underlying moisture source should be identified.

HVAC Tips for Fall Allergy Season

1. Check Your Filter

After months of summer cooling, September is a sensible time to inspect your HVAC filter.

A dirty, overloaded filter will not work as effectively. The EPA recommends using at least a MERV 13 filter, or the highest-efficiency filter the system’s fan and filter slot can accommodate.

That does not mean every homeowner should automatically install the highest-rated filter available. A filter needs to be compatible with the heating and cooling system so that proper airflow is maintained.

2. Keep Pollen Outdoors When Possible

During high-pollen periods, keeping windows closed can limit one pathway for outdoor allergens to enter the home.

Changing clothes after spending significant time outdoors, removing shoes near the door, and cleaning pets after outdoor activity can also help allergy sufferers reduce the amount of pollen brought inside.

3. Watch Your Indoor Humidity

A small humidity gauge can help you monitor conditions rather than guessing.

If indoor humidity remains high even when temperatures are comfortable, a professional may need to look at your air conditioner, ventilation or humidity-control needs.

4. Pay Attention to Airflow

A clean filter cannot do its job effectively if the rest of the system has airflow problems.

Blocked registers, ductwork issues, equipment condition, and system design can all affect how conditioned air moves throughout the house, impacting humidity levels.

5. Keep Up With HVAC Maintenance

Routine HVAC maintenance provides an opportunity to check the system before regular heating season begins.

A technician can inspect equipment operation, airflow and system components and identify concerns that might otherwise be overlooked until the equipment is working harder.

6. Look at Indoor Air Quality as a Whole

Filtration is only one piece of cleaner air.

The EPA identifies three main strategies for improving indoor air quality, including the use of HEPA filters. source control, ventilation and filtration or air cleaning. Depending on the home, whole-home filtration, ventilation or humidity-control equipment may complement the existing HVAC system.

The goal should be to address the needs of the individual home rather than assuming one product will eliminate every allergen.

Boost Your HVAC System’s Role in Indoor Comfort

Fall allergies begin outdoors, but pollen and other particles can easily find their way indoors. Your HVAC system cannot eliminate seasonal allergies, but proper filtration, airflow, humidity control and HVAC maintenance can support a cleaner and more comfortable indoor environment.

September is an especially good time to check the air filter, monitor humidity levels, and pay attention to changes in airflow as your HVAC unit transitions out of the summer cooling season.

Ready to improve the comfort and indoor air quality of your Connecticut home? Visit RalphMannandSons.com to learn more about Ralph Mann & Sons’ HVAC and indoor air quality services.

Sources: including studies on air purifiers and the effectiveness of HEPA filters in reducing indoor allergens. U.S. Environmental Protection Agency (EPA); Asthma and Allergy Foundation of America (AAFA); American College of Allergy, Asthma and Immunology (ACAAI); Centers for Disease Control and Prevention (CDC); Ralph Mann & Sons.