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Winter Allergies and Your HVAC System

When people think of allergies, spring pollen usually comes to mind.
But for many homeowners, allergy symptoms actually get worse during winter.
If you’re sneezing, coughing, or dealing with dry, irritated sinuses when the heat is on, your HVAC system may be playing a role.
Understanding how winter allergies work—and how your heating system affects indoor air quality—can help you breathe easier all season long.
Why Allergies Can Be Worse in Winter
During winter, homes are sealed tightly to keep cold air out.
While this improves energy efficiency, it also traps allergens indoors.
Unlike seasonal outdoor allergens, winter allergies are usually caused by indoor irritants.
Common winter allergy triggers include:
Dust and dust mites
Pet dander
Mold spores
Dry air irritation
Indoor air pollutants
Because your HVAC system constantly circulates air, it can either reduce these allergens—or spread them throughout your home.
How Your HVAC System Affects Winter Allergies
Your heating system is responsible for moving air through your home.
If it isn’t properly maintained, it can worsen allergy symptoms instead of improving comfort.
Air Circulation and Allergen Spread
Forced-air heating systems circulate air through ductwork and vents.
When dust, dander, or mold builds up inside the system, those particles get redistributed every time the heat runs.
Dirty Filters and Poor Filtration
Clogged or low-quality air filters allow allergens to pass through easily.
Over time, this leads to higher concentrations of airborne particles and increased allergy symptoms.
Dry Indoor Air
Heating systems reduce indoor humidity, which can:
Dry out nasal passages and sinuses
Make allergy symptoms feel more severe
Increase irritation of the throat and eyes
Dry air doesn’t cause allergies, but it can make existing symptoms much worse.
The Role of HVAC Filters in Allergy Control
Your HVAC filter is one of the most important tools for managing winter allergies.
High-quality filters can:
Trap dust, pollen, and pet dander
Reduce airborne allergen levels
Improve overall indoor air quality
For allergy-prone households, filters with higher MERV ratings are often recommended.
However, these filters must be changed regularly to prevent airflow restriction and system strain.
Most homes should replace filters every 1 to 3 months during winter, depending on usage and indoor conditions.
Ductwork and Hidden Allergens
Even with a good filter, allergens can accumulate in ductwork over time.
Duct-related allergy problems may come from:
Dust buildup
Mold growth caused by moisture
Air leaks pulling contaminants from attics or crawl spaces
Old or damaged insulation inside ducts
Sealing and cleaning ductwork can significantly reduce the amount of allergens circulating through your home.
Mold Growth and Heating Systems
Mold is a major indoor allergen and can be especially problematic in winter.
Condensation, humid basements, or neglected HVAC components can create the perfect environment for mold growth.
Signs mold may be affecting your air quality include:
Musty or earthy odors when heat runs
Persistent allergy symptoms indoors
Visible mold near vents or HVAC equipment
Professional HVAC inspections can identify moisture issues and prevent mold from spreading through your system.
How to Reduce Winter Allergies With Your HVAC System
If winter allergies are affecting your comfort, your HVAC system can be part of the solution.
Steps homeowners can take:
Replace air filters regularly
Schedule annual heating system maintenance
Keep vents and returns clean and unobstructed
Use a whole-home humidifier to balance moisture
Seal duct leaks to prevent contaminant entry
Consider air purification or UV systems
These improvements help create cleaner air while improving heating performance and efficiency.
When to Call an HVAC Professional
If allergy symptoms persist despite basic maintenance, it’s time to bring in a professional.
You should schedule an HVAC inspection if you notice:
Excessive dust buildup
Uneven heating or weak airflow
Strange odors when the system runs
Worsening allergy symptoms indoors
An HVAC professional can identify airflow issues, filtration problems, or hidden contaminants affecting your indoor air quality.
Final Thoughts
Winter allergies are often an indoor air quality issue—and your HVAC system plays a major role.
With proper filtration, humidity control, and regular maintenance, your heating system can help reduce allergens instead of spreading them.
At Twintech Heating & Cooling, we help homeowners improve comfort and air quality during the winter months.
If you’re struggling with allergies while running your heating system, professional HVAC solutions can make a noticeable difference in how you feel at home.
Received a new range and needed someone to disconnect the old range and connect the new gas range. They did a thorough job and were kind enough to remove the old range from the house. Thank you!
Very satisfied with this company! Salesperson Dave was very good, very knowledgeable and gave me the impression that he wanted to sell me what I needed rather than what would put the most money in the company's pocket. He also called back after the installation to see if I was satisfied with the result. The installation crew of Greg, Grant and Peter did a great job. They arrived on time, completed the job quickly, answered all my questions and thoroughly cleaned up. They told me to call if I had any further questions. They left me with the impression that they really cared about their work and my satisfaction and that it wasn't " just a job". Prior to researching for a new furnace, I had never heard of this company but I'm glad that I did and would highly recommend them to anyone looking for a new furnace or air conditioning unit. They may be small but they do a great job!!
I first met Greg and Grant (The Twin Brothers from Twin Tech - yup -it's not just a cool company name) back in 2014 when our furnace broke down and they installed our Carrier Furnace and AC that we purchased through Sears. I liked them instantly when I met them due to their friendly and professional service, and the fact that they didn't mind taking a little extra time to explain things in terms I could understand. Since that time they have reached out to me at least once a year to ensure that everything was running smoothly with my system and to keep me appraised of their evolving services. Due to this high level of proactive customer service I didn't hesitate to call and obtain their help for a Gas Stove removal and installation. When I scheduled the call Greg and Grant let me know that they would arrive the morning of the appliance delivery to disconnect the old gas stove, and then return in the afternoon to connect the new stove. Sure enough, they did just that as promised. Where they exceeded my expectations is with the extra level of support helping to assemble the burners and grills on the stove and in the oven. This may seem like a small thing to some but to my wife who was at home during this entire process it meant a stress free transition to the meal prep for the day. When I called home to ask about the install she commented that, "they left the place cleaner than it was when they arrived and they setup all the grills on top of the stove and in the oven... they didn't have to do all that -Wow!". You know what they say, Happy Wife, Happy Life. So in summary, I am recommending Twintech Heating & Cooling for all of your Furnace, Air Conditioning, and Gas Line needs. I've even called on these guys to help swap out a leaky water valve. They are just so easy to reach and communicate with by phone, and they don't mind a text message to confirm the details. You can rest easy when you have the Twins on your side as an extension of your household maintenance plan.
First thing, they actually showed up for a quote. Other big name companies in the area didn't even return my call , job was done as expected and new equipment is quiet and installed very clean and professional. Would highly recommend these guys.
They removed our old furnace and replaced it with a new furnace and AC system.
Work was performed in a clean and timely manner. The furnace and metal work was performed by the Twintech team (did not require separate contractor to do the metal work). Energy audit was arranged and promised rebates were received. The overall price was very competitive. We have recommended Twintech to several of our friends and family. Awesome job.
Grant and Greg installed a heating and AC system in our new Linwood post and beam home. Post and beam can be challenging structures for running ductwork and their high ceilings and open concept frequently frustrate efforts at balancing air flow and controlling temperatures. But these guys did it and did it right the first time. Even the building inspector was impressed with what he saw. More importantly, the boys brought a high degree of trust and integrity to the job. Something in short supply these days.
Very polite and professional. They removed my o
ld furnace and A/C and installed my new ones. They were efficient and thoroughly cleaned up when they were done! I would highly recommend them!
Pro from start to finish. They were able to fix my gas fireplace at very little cost as well.
Excellent installation very knowledgeable gentlemen! Would highly recommend them to all my friends for any hvac work !
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We are very happy to recommend this company to everyone. Our furnace broke down on Sunday morning. We phoned them and before noon Grant the owner showed up. He worked on the furnace for about a hour not wanting to give up to fix the problem. The furnace was 17 years old. I was the one talking about replacing it. End result was the next day it was all done. On the Sunday Bob came over with heaters to warm up the house. We decided to replace the water heater at the same time. Thanks Grant for the excellent work. Thumbs up.
Right on time. Explained how to work the HRV in a different way so the house would not be so dry. Changed my whole house water filter for me as well. Friendly, helpful, caring service!
Very pleased with the professional service that TwinTech Heating and Cooling provided in replacing my furnace. I got several quotes from different service providers. Their price was excellent and they explained the features very well. We are very glad we went with TwinTech and highly recommend their services.
We were new homeowners in need of a second opinion. TwinTech Heating & Cooling were Amazing and professional. Very knowledgeable and great service all around. Recommend to anyone looking for honest and reliable services. Treated with respect and care. Thank you Greg, Mitch and Bob!
TwinTech is an excellent and honest company! I called them for a second opinion after being told by another company that I needed to replace my furnace. Turns out this was not the case at all! I did not need a new furnace. TwinTech did not push to make an unnecessary sale and saved me from a huge expense. Bob and Mitch were extremely professional and above all honest! I definitely recommend TwinTech!
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