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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.
Fantastic team. Completed the job as per the specifications and in under 3 hours. Highly recommended Twintech.
During the summer, I previously hired TwinTech to replace my air conditioner when it failed. They did an excellent job so when I decided to proactively replace the furnace I contacted them. The furnace I had was 22 years old and showed signs of internal leakage. It still worked but rather than wait to have it fail in cold weather, I decided to purchase a higher efficiency model before it failed and take advantage of energy efficiency rebates. TwinTech offered very useful advice on the make and model of furnace to choose including high efficiency and variable speed motor. The price was reasonable, TwinTech arrived at the allotted time, installed the new furnace (including some re-routing of exhaust lines since the existing ones were too close to other vents), removed the old furnace, tested the installation and cleaned everything up. Overall, it was a good experience, they did a great job and the new furnace is working well.
Greg came over at 9:30pm to rescue my daughter and I from a horrible experience with Enercare that evening. He was professional. Kind. And got us what we needed quickly and at an afford price. I would 100% recommend calling on Greg and his team for any of your heating and cooling needs in the future!!
Installed a great hot water heater when our old one failed. When my furnace died during cold weather they showed up quickly and my house was warm before my wife got home. :)
I dont usually right reviews but when you receive service like this I felt it was a must. Honest and fair. I Have 4 children and on Xmas eve my furnace stopped working and a gentleman came out and got me up and running so at least we would have heat for the holidays. As promised he would replace my furnace early in the new year. The job was completed on time, great price for quality furnace and extremely clean and professional job. Would have never known anyone was in the house. Not a spec of dust or mess from lugging out an old rusty furnace. If you have any ac or heating concerns twintech is your only option. I was royally impressed with and Im sure you will be too.
Class Act ! These guys were professional right from the quote stage through to installation. They know their stuff and took their time to help educate me. They take pride in their work and it shows. I would recommend TwinTech Heating and Cooling to anyone. Keep up the great work !!!
This Company is terrific. No high pressure sales and they deliver exactly what they promise to deliver. The new furnace is great and we now get consistent temperatures throughout the house. The installers were great and very efficient and completed the work on schedule on the promised day. Everyone representing this company was very aware of their presence in our house and worked diligently to keep our home as uninterrupted and as clean as was humanly possible. We did not need to go around the house to clean up after they left, what a nice surprise. We have had follow up by the company to ensure everything is to our satisfaction. How unusual in today's environment. The impression left by Twintech is that they care about us and our home. This is so refreshing in today's high tech world. Out thanks go out to Dave in sales and G, G, and P (the installers).
They were Timely and professional. They were very Knowledgeable with answering all of my questions.
The entire process was prompt and professional, from the initial quote to the installation of the new furnace. The team installed the new furnace and removed the old one in approx. 4 hrs. The guys were very knowledgeable and gave me lots of information. I have used Twintech before for a new A/C installation and new I was in good hands.
The overall experience dealing with this company was great from start to finish when getting a new furnace and ac this year. Everything was clearly explained to us during our consultation with Dave and there were no surprises with added costs. The work was done as expected and their response time to inquiries were very timely generally within a few hours or less. They are all very professional and was a pleasure to do business with them. Highly recommend to anyone looking for honest quality professional service.
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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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