[BACK]
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.
We are very happy with our new furnace. The service was excellent the guys worked 6 hours straight through and there was no mess at all they took the old furnace boxs etc with them they then explained everything to us they were very helpful and pleasant , when we need a new air conditioner we know who to call!
The crew from sales to installation was very professional and had great attention to detail
We couldnt have been more impressed with Twintech - from our first service call with Mitch who took the time to thoroughly diagnose the issue with our furnace, to Dave who proposed a well thought out solution to meet our needs and finally Greg and team who acted quickly to install given we had no heat.
We did our due diligence by soliciting quotes from alternate providers and were shocked and disappointed by the aggressive and manipulative tactics used.
Twintech was honest in their approach, detailed in their product knowledge, reasonably priced, diligent in their follow-up and valued our business.
Well done Twintech! You made this a positive experience for us and our new furnace works beautifully!
We recently purchased an Amana high efficiency furnace and humdifier through Twintech. The work was completed very professionally and the quality of the workmanship was high. There was some additional sheet metal work required to complete the installation, which they were able to complete themselves. Overall I am very pleased with the work and would highly recommend Twintech for a furnace replacement.
We were very pleased with every aspect of the work that was done. They were very professional and polite. They arrived when they said they would and job was completed on estimated time
We would highly recommend them to whoever needed a recommendation
We have a very large dog and they were very understanding and respectful of him being around
The blower on our furnace stopped working leaving us with a cold house. Dave from TwinTech responded immediately to our HomeStars service request. From beginning to end Dave was nothing but helpful, friendly and professional, he did a great job of walking us through the quote and scope of work.
The replacement of the furnace went smoothly. The Guys did a great job, everyone was very friendly and polite. There were no hiccups, or unexpected costs. The only surprise was they left the work area cleaner than it was before they started.
Was a great experience with the whole TwinTech team. Its been a couple of months since the new furnace has been installed and its working great!
I heard about TwinTech when researching new furnaces at furnaceprices.ca. After contacting them about my broken down furnace, Dave came to my house the next day to assess my situation and requirements for a new furnace. He recommended one that had stainless steel heat exchangers which sold me since my previous furnace had issues with a rusted secondary heat exchanger that had to be replaced. Dave also set me up with an appointment with an energy audit company so that I could take advantage of a rebate to help improve the energy efficiency of my home and get some money back. A few days later, Greg, Grant, and Mitch came to install the new furnace and remove the old one. When delivering and removing the furnaces, they were very careful not to damage my floors and walls, and even laid out red carpeting to protect the floors. They were very friendly and professional. The installation was completed in the time they said it would take and they cleaned up their work areas. Within a week, Dave called to follow-up to see how everything was going. I have already recommended them to several friends and family members who may need new furnaces soon.
Twintech did a great job, from Dave the Sales Rep to the Office staff and The Professional Technicians who did the installation. They were professional, courteous, knowledgable and informative. From beginning to follow up we were completely satisfied with everything. Thanks Again. Sincerely The Laytons
Great product, great service, great follow-up. The Twintech Heating and Cooling arranged removal of my existing oil tank and they installed the new gas furnace Amana (made in USA). I am very happy with the final result and support I received throughout the process. My thanks go to the entire Twintech team for their professionalism, great communication and follow-up.
We've had Twintech provide us with work in the past, for an inground pool heater and required rough-in for a new gas stove. More recently they provided the same friendly, professional, timely and clean installation of our new furnace.
Related Links:
oshawa gas furnace problems, ac service call, pickering hvac prices, local ac services, ajax furnace inspection, ac repair services, whitby furnace replacement, furnace repairs pickering, oshawa hvac furnaces, central ac service, ac unit maintenance, pickering gas furnace problems, ac installation near me, ajax hvac repair, hvac repairs, ac contractors, ac repair and service, whitby furnaces, residential furnace, residential ac repair, pickering hvac furnace, pickering furnace service, pickering furnaces, oshawa furnace inspection, oshawa furnaces, nearby ac repair,
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!
Deciding whether to get an extended warranty for your AC depends on a few factors. Firstly, consider the age of your AC unit and its reliability. If it's relatively new or from a reputable brand known for longevity, you might not need one.
Read MoreTo keep your air conditioner running efficiently and to avoid unnecessary costs or potential damage, here are some tips on how not to use your air conditioner this summer: 1. Don't Set the Temperature Too Low Setting your AC to an extremely
Read MoreKeep in mind that a professional inspection by an HVAC technician is the most reliable way to assess the installation. Here are some things you can check: Outdoor Unit Placement: The outdoor unit should have enough space around it for proper ai
Read MoreSo am cleaning my window AC. Was wondering is there a way to open up the front panel fully My guide only shows how to pull out the filter and the part where it is. Cause it definitely needs cleaning further behind. I checked from the outsid
Read More