Can Your HVAC System Make Your Allergies Worse in Winter?

If you're wondering whether your HVAC system can make your allergies worse in winter, the answer is yes. Your heating and air conditioning system can make your allergies worse if it has dirty filters, excess moisture, or contaminated parts that let allergens get pumped all around your house. But if your heating and A/C system is always properly maintained, it can really help improve the air quality in your home by filtering out airborne particles and keeping the humidity low.

If you live in the North DFW area, including Lewisville, Flower Mound, or Highland Village, then you're probably all too familiar with how quickly Texas weather can change. One day you're running the AC, and the next you're turning on the heating to escape a cold front.

You might not know that your HVAC system can actually help with common Texas allergies. But what if you start sneezing, coughing, or experiencing sinus problems whenever the heat comes on? Your heater and AC could be contributing to the problem.

Here's what you need to know about winter allergies and how your heating affects indoor air quality, as well as what you can do to breathe easier at home.

Key Takeaways:

• If you don't change your HVAC filters regularly, more allergens will circulate around your home.

• Lots of things can contribute to indoor allergies, including dust, pollen, pet dander, and mold spores.

• High humidity in the house gives dust mites and mold spores the perfect breeding ground, while dry winter air can irritate your nose, throat, and nasal passages.

• Investing in the right air filters and regular maintenance of your HVAC system can help improve the air quality in your home.

• If your allergy symptoms get a lot worse when your A/C or heating kicks in, your HVAC system probably needs some attention.

Why Do Your Allergies Get Worse When You Turn On the Heating?

When you turn on your heating system, it circulates warm air throughout your home. Unfortunately, that moving air can often carry dust, pollen, pet dander, and other allergens.

During the warmer months, particles can accumulate on surfaces and inside parts of your HVAC equipment. Then, when you start using your heating more often, this increased airflow can disturb some of the dust and move it around your home.

Common indoor allergens include:

• Dust mites: Tiny creatures that live in bedding, carpets, and upholstery. Their waste particles can trigger allergic reactions.

• Pet dander: Microscopic skin particles that are shed by pets and can circulate through your HVAC system.

• Mold spores: Damp areas can encourage mold growth, releasing spores that might trigger your allergy symptoms.

• Pollen: Outdoor allergens can enter your home on your clothing, shoes, and pets, even when you keep the windows closed.

The Environmental Protection Agency (EPA) explains how indoor pollutants affect air quality and why controlling their sources is really important.

Can Dirty HVAC Filters Make Winter Allergies Worse?

Yes, dirty HVAC filters can make your allergies worse. Your air filter is the first line of defence against airborne dust, pollen, dander, and other irritants, so when it gets clogged up with debris, it restricts airflow and makes your AC unit work a lot harder. A clogged air filter can also reduce your system's ability to catch more particles.

Make sure to check your filters every month and replace them as often as the manufacturer advises; often every 1 to 3 months. You may need to change them more often if you use your AC a lot in the summer or have a lot of dust and pet hair around the house.

You might also want to consider stepping up your filtration. The EPA's guide to residential air cleaners explains how MERV ratings help you compare filters. Generally speaking, higher-rated filters catch more particles, but you should make sure your HVAC system can handle the extra airflow requirements.

HEPA filters, or high efficiency particulate air filters, can catch at least 99.97% of particles measuring 0.3 microns under their specified test conditions. That said, you shouldn't put a high-efficiency filter in your central AC unit without checking it's compatible first.

Image credit: Heiko Ruth, Pexels

Can Mold In Your HVAC System Affect Your Allergies in Winter?

Yes, if you're an allergy sufferer, mold inside your HVAC system can trigger your allergy symptoms in the winter months.

If your AC system is clogged up and can't drain properly, that moisture can encourage mould to grow. Although your heating system doesn't normally produce the same condensation as your air conditioning system, moisture can remain around the AC evaporator coil and other components.

Watch out for these warning signs:

• A musty smell when your HVAC unit turns on

• Visible mould around vents or parts of the system that are easy to get at

• Water collecting near the unit

• Weak airflow or high indoor humidity

• Your allergy symptoms seem to get worse when your air conditioning runs

The EPA's mold guidance explains how moisture control plays a really important role in stopping mould problems.

If you notice a musty smell or think there might be mould inside your air handler, don't just try to spray some household cleaner into the equipment. Get an HVAC pro in to check out where the moisture is coming from and tell you what you need to do to fix your indoor air quality problem.

Should You Have Your Air Ducts Cleaned Before Winter?

It's not always necessary to get your air ducts cleaned before winter to keep your allergies at bay. Yes, dust can build up inside your air ducts, but getting them professionally cleaned might not make a big difference in terms of how you feel. Unfortunately, routine cleaning just doesn't have proven health benefits for most people.

That being said, there are a few situations where professional duct cleaning might be a good idea, especially if they're visibly contaminated with mold or clogged with a lot of dust and debris that's making its way into your living space and resulting in poor indoor air quality.

How Can You Improve Indoor Air Quality During a North Texas Winter?

The good news is you don't necessarily need to break the bank to make your home a more comfortable place to be. Just start by getting into a few good habits:

1. Replace your HVAC filters regularly. Check them monthly and use a filter that suits your heating and cooling equipment. This should also be a job involved in preparing your HVAC system for a North Texas winter.

2. Schedule professional heating maintenance. A technician can inspect airflow, filters, and accessible components before the cold weather arrives. We recommend The Joey Club, our annual HVAC maintenance service that includes two full-system inspections a year from the same expert who knows your unit inside and out, plus priority service when you need us most.

3. Monitor indoor humidity. Aim for 30% to 50% where practical, so you're balancing comfort and moisture control.

4. Keep dust under control. Vacuum regularly and clean surfaces to reduce dust mites and pet dander.

5. Consider additional air filtration. A suitable portable HEPA air cleaner can help capture airborne particles in your bedrooms and other rooms that you use a lot.

If your allergy symptoms persist even after you've made these changes, or if you're struggling with severe allergies, it's a good idea to speak with a healthcare professional to see if there's something else going on. Your HVAC system might be contributing to your discomfort, but it's probably not the root cause.

Let Koala-T Help You Breathe Easier at Home

Your heating and cooling system should be making you feel more comfortable, not worse. At Koala-T Heating and Air, we want to help you understand how your HVAC system might make your allergies worse in Winter.

Having operated for over 40 years, we're a Texas HVAC license holder (TACLA00153892E) and are accredited by the Better Business Bureau. We do things the simple way: you talk to a real person when you call and receive an up-front quote with no hidden fees. If we can't fix the problem, we'll give you a 100% refund.

Want to know what's going on with your home's air quality? Give us a call to schedule an HVAC inspection.

FAQs

Q: What type of air filter is best for allergies?

A: Generally speaking, filters with a higher MERV rating will catch more of the airborne particles that are affecting your allergies, but don't just go for the highest rating you can find. You don't want to end up restricting airflow too much by choosing a filter that's still too dense. It's worth talking to your HVAC technician to see which one is the best bet for your system.

Q: Why do my allergies get worse when I turn on the heat?

Your heating system has probably not been in use for months, and when you switch it on, all the dust that's built up inside will travel around your home. If your filters need to be replaced, that's probably part of the problem. Dry air indoors can also be a nuisance, especially when you have allergies. Check your filter and get your humidity levels sorted first. If things persist, it's worth getting a pro to take a look.

Q: How often do I need to get my HVAC system serviced if I have allergies?

You should arrange regular HVAC maintenance and check your air filters more often if allergies are affecting your household. Booking a cooling system inspection in the spring and a heating inspection just before winter gives you two opportunities to catch any issues with drainage, airflow, and filtration early on. Between visits, keep those filters clean and keep an eye out for musty smells or unusual humidity levels. These simple steps should help you maintain good indoor air quality all year round.