Seasonal allergies in St. Louis? Your HVAC system might be making symptoms worse. Learn the signs and how to improve indoor air.
A poorly maintained or outdated HVAC system can circulate dust, pollen, pet dander, mold spores, and other airborne allergens throughout your home. In this post, we’ll walk through the key signs that your HVAC system is aggravating allergies, why it happens, and how you can take action to create a cleaner, healthier home environment.
Response from the owner:Thank you, Hank, for your wonderful feedback; we're glad you enjoyed the fast, friendly, and professional service, and we'll be sure to keep up the great work!
I called on December 25th at midnight and started leaving a message and Thomas Hoffman the owner called me back almost immediately. He said he would come out the next morning between 8:00 and 10:00 am snd he was promptly on time. He fixed my problem and while he was there I decided to get an estimate for a new furnace and air conditioning unit. The price was very reasonable and the installers one of them being his son were both very professional very courteous, polite, arrived on time and finished the same day. I enjoy knowing that I now have the support of Thomas Hoffman heating and air conditioning along with the peace of mind that comes with owning a Trane. Nothing stops a Trane.
Albert Koesterer
Response from the owner:Albert thanks so much for your kind reviews and your business. We truly appreciate it!!!
The Thomas Hoffmann team did a great job taking care of our semi annual HVAC maintenance. They not only worked with us to schedule the visit, but also did an excellent job sending us reminders on when they would be out.
Response from the owner:Thank you so much for the great review, Bob! We appreciate your support and are happy to hear you had a great experience!
Nick was excellent. Super profession, quick, and up front with the pricing (which was fair). Hopefully we don't need to call anyone to fix our AC again, but if we do - I'm calling Nick!
Response from the owner:Thank you, Layton, for your amazing review! We really appreciate your support and hope to be your first call for any future repairs!
Same day service. Technician arrived as scheduled. Replaced capacitor quickly. Friendly technician. Repair cost $429 seemed high for inexpensive part and 20 minutes labor.
Response from the owner:Thank you, Tom, for your feedback! We're glad to hear the technician was prompt and friendly, though we understand your concerns about the repair cost. We appreciate your insights and hope to serve you again in the future.
Response from the owner:Thank you so much, Al, for your excellent review; we truly appreciate your support and are glad to hear you had a great experience!
Thomas Hoffmann is the most professional and courteous of all the HVAC companies in St. Louis. It has kept my HVAC systems in good working order through the hottest and coldest days for many years.
Response from the owner:Thank you, Jonathan, for your kind words about our professionalism and courtesy; we truly appreciate your support!
I notified two companies at the same time regarding a malfunctioning AC unit and Wow! Super fast response from Hoffmann on a weekend no less, to fix our AC unit. Hoffmann’s tech responded to my call immediately and fixed our AC before Galmiche has even responded. Used to be a Galmiche customer, but will use Thomas Hoffmann from here on out!
Response from the owner:Thank you, Darlene, for your fantastic feedback! We're glad to hear that our team was able to respond quickly and resolve your AC issue. We appreciate your trust in us moving forward!
Ryan did a great job with my AC reinstall. Very knowledgeable company with Tom Hoffmann providing the engineering expertise.
Response from the owner:Thank you, Steve! We're glad to hear that Ryan did a great job on your AC reinstall, and we appreciate the shoutout to Tom's expertise. Your satisfaction means a lot to us!
These guy's are amazing same day service very well priced for the knowledge they have ask before doing anything to confirm they're my new go to
Response from the owner:Thank you, Cory! We're glad you found our service amazing and appreciate your kind words about our pricing and knowledge. We're here for you anytime!
Great service. Responsive. Well trained technicians. Honest friendly and thorough. I highly recommend Tom Hoffmann and his team.
Response from the owner:Thank you for your kind words! We appreciate your recommendation and are delighted to hear about your positive experience with our team.
My ac compressor was replaced. They always do a good job and they are always available when you need them.I think the price was a little too high since they only had to change the compressor in my unit. The compressor was under the warranty. Other than that Im very satisfied with the job the technician did.
Response from the owner:Thank you, Carlos, for your feedback and for recognizing the hard work of our technician; we appreciate your satisfaction with the job done and will take your pricing comments into consideration.
I was very pleased with your service. Prompt response would was most appreciated. The technician was very knowledgeable and prepared for the work. Also he was very personable and professional.
Response from the owner:Thank you, Richard, for your kind words; we appreciate your recognition of our technician's knowledge and professionalism, and we're glad you had a positive experience with our service.
Thank goodness for them coming out so quickly. Got our whole job done and we are COOL again. Thanks so much!!!
Response from the owner:Thank you, Sandy! We're so glad to hear everything got done quickly and you’re feeling cool again. We appreciate your kind words!
Had an amazing experience with Thomas Hoffman. They were very professional and solved the problem quickly. I would highly recommend!
Response from the owner:Thank you, Alex, for your wonderful feedback! We're glad to hear that Thomas was able to assist you so effectively. Your recommendation means a lot to us!
Zac did our service today. A very professional and courteous young man. He did a thorough inspection and cleaning on our HVAC system.
Response from the owner:Thank you, Tom, for your kind words about Zac's professionalism and thoroughness during your HVAC service; we appreciate your feedback!
I've used these guys twice now and their response time is great, they are friendly, informative, and most importantly, effective. I'm calling these folks every time my furnace sounds weird.
Response from the owner:Thank you for the wonderful feedback, Greg! We're glad to hear that you've had such positive experiences with our team. Providing timely and effective service is our priority, and we're here whenever you need us. Looking forward to assisting you again!
Excellent place to work with and installation crew were A+. They were able to get my new AC and Furnace installed quickly. I have breathing issues and disabled so this was a GREAT experience. If you need AC or Furnace installed this is your place.
Response from the owner:Thank you, Tony, for your wonderful feedback! We're glad to hear that our installation crew made the process smooth and efficient for you. Your satisfaction means a lot to us, and we appreciate your recommendation!
Zachary was very friendly, efficient and knowledgable. He was able to service both units in 1 hour. I would recommend Thomas Hoffmann A/C for any future needs for me.
Response from the owner:Thank you, Michael! We're glad to hear that Zachary provided you with friendly and efficient service. We appreciate your recommendation and look forward to assisting you with any future needs.
Thomas Hoffman air-conditioning and heating is so wonderful and professional! Nick Hoffman was the technician that diagnosed my malfunctioning air conditioning system and determined how to fix it. He was so incredibly professional and even invited me to watch while he worked, and kindly explaining to me all the details about the problem and how he is fixing it. I am now a client for life with this company because of how professional, knowledgeable, and a delight to work with they are! I want to add that they prioritized helping me on the same day that I called and even was a holiday (and 90 degree heat out!), so that is another outstanding Effort from this amazing company! Thank you so much.
Response from the owner:Thank you, Carrie, for your wonderful feedback! We're delighted to hear about your positive experience with Nick and our team. Your satisfaction is our priority, and we're glad we could assist you on the same day. Welcome to our family of clients!
They were able to come out quickly to help when our AC went down in the heat! They were prompt, kind, knowleadgable, explained everything easily in ways I could understand, fixed the issue, and made the experience so easy! I felt comfortable with the technican in and around our home working. Nick took the time to answer some questions about an unrlated issue while there. They will always be who we call for our heating and cooling needs!
Response from the owner:Thank you, Erin, for your wonderful feedback! We're glad to hear that our team, especially Nick, was able to assist you promptly and make the experience comfortable and easy. Your trust in us for your heating and cooling needs means a lot!
I highly recommend Thomas Hoffmann for anything involving HVAC. The person replacing my furnace, Britton Buehrig, was Professional and took pride in his work. The job was very cleanly done.
Response from the owner:Thank you, Ray, for your kind words and recommendation! We're glad to hear that you were provided with professional service and a clean installation. Your satisfaction means a lot to us.
Excellent service. AC went out on a hot summer day, hooked up with them through Angi, and within 2 hours they had arrived and fixed the problem. Can't ask for more than that
Response from the owner:Thank you for your kind words! We're glad we could help you quickly on that hot summer day. Your satisfaction means a lot to us!
Nick Hoffman was great. He came short notice to fix a leaky air handler did it quickly and efficiently and also took a look at the AC plan on using them again for our service of our HVAC
Response from the owner:Thank you, Jenny, for your kind words about Nick and for trusting us with your HVAC needs; we're glad to hear he was able to assist you efficiently!
Super company to deal with. Always professional, knowledgeable and friendly. Zachery was my technician and explained everything he did throughly and in a manner I could understand. Very nice guy.
Response from the owner:Thank you, Maggie, for your kind words! We're glad to hear that Zachary provided you with excellent service and clear explanations. We appreciate your support and look forward to helping you again!
My a/c was not working correctly and I knew it needed to be serviced. The person came and cleaned what needed to be cleaned and he did what he could for the output. He was very professional and nice. We will definitely call them for our future needs.
Response from the owner:Thank you for the positive feedback! We're glad to hear that you were pleased with our prompt and friendly service. We look forward to assisting you again in the future!
Nick arrived to repair our ac earlier than expected. He quickly diagnosed and made the necessary repairs. The cost was reasonable. We will definitely contact Thomas Hoffmann for hvac services in the future..
Response from the owner:Thank you, Michael! We're glad to hear Nick provided prompt and efficient service, and we appreciate your trust in Thomas Hoffmann for your future HVAC needs.
We have used Thomas Hoffman Air Conditioning and Heating for AC issues for the last two years. We have been so happy with the service we have received both times. This year, we just needed a little maintenance as our unit wasn’t working to its full potential. I called first thing in the morning and was able to get a same day appointment! Nick was so personable and knowledgeable, and he got us back up and running and no time. Thank you again for saving us from the summer heat!! We are so grateful for the amazing customer service you guys provide!!!
Response from the owner:Thank you so much, Teri, for your kind words and for trusting us with your AC needs over the past two years; we're glad Nick could help get your unit back to its best, and we truly appreciate your gratitude for our service!
I txt Thomas Hoffman air-conditioning and heating Sunday early evening about 6:30 and just left A detailed message of what was going on with my AC I received an automated reply, saying they would contact me soon. I heard from them the next Morning at 11 AM to confirm what was going on with my unit and said they would have a Tech out today still but would be the last call between 6 and 8pm. I expected to get an appointment 2 to 3 days later. We’re in the middle of about an 8 to 10 day Heat wave of Mid to upper 90s. So imagine my surprise when I received a call from Zachary at 3:20 telling me he was in Saint Charles and was on his way to my house to look at the unit. When I explained what was wrong on the phone, he was pretty confident. He knew what it was once he got here, pulled off the cover and sure enough it was the capacitor. Pull the old one off and install the new one turned it back on and boom I have cold air blowing. I would highly recommend Thomas Hoffman, AC and heating and if you can request a certain Tech Zachary is your guy he is great super Frndly got the job done quickly and even interacted with my dogs Who are super friendly
Response from the owner:Thank you, Vicki, for sharing your experience with us! We're glad to hear that Zachary was able to resolve your AC issue quickly and that he made a positive impression on both you and your dogs. We truly appreciate your recommendation and look forward to assisting you again!
We can’t say how happy we are with the quick and efficient service! We came home Friday evening after work on a 95 degree day (with a week of 90 degree weather ahead) and our A/C was totally out. We called this small business owner around 6pm and he was here by 7:25. He replaced our wires, had cool air running, gave us some helpful tips for the future, and was already out the door by 7:50. He was very polite, friendly, straightforward, and saved our evening/weekend!
Response from the owner:Thank you, Morgan, for your wonderful feedback! We're glad our team could provide quick and efficient service to keep you comfortable during the heat. Your satisfaction means a lot to us!
1. You’re Experiencing Allergy Symptoms Indoors — All Year Long
If you notice that allergy symptoms persist regardless of the season, your indoor air quality may be the culprit. Common indoor allergy symptoms include:
Sneezing
Runny or stuffy nose
Itchy eyes or throat
Skin irritation
Frequent headaches
Your HVAC system could recirculate airborne irritants like dust mites, mold, or dander. Without proper filtration and regular maintenance, allergens can thrive inside your home and your ductwork.
2. You Notice Excessive Dust Around Vents and Furniture
A telltale sign of a compromised HVAC system is a noticeable layer of dust, especially near air vents. If dust builds up quickly after cleaning, your system may not filter the air effectively. This can happen if:
Your HVAC filter is clogged or of too low quality (e.g., low MERV rating)
Your ductwork is dirty or leaking
Your air returns are pulling in unfiltered air from dusty areas like attics or crawl spaces
This dust isn’t just a nuisance — it’s a vehicle for allergens like pet dander and pollen to circulate through your home.
3. Your Air Filter Is Dirty (or You Can’t Remember the Last Time You Changed It)
Your HVAC filter is your home’s first line of defense against allergens. But if it’s clogged or outdated, it can no longer effectively trap particles. It can restrict airflow, forcing your system to work harder and potentially blowing allergens into your home.
We recommend St. Louis homeowners:
Change filters every 1–3 months
4. A Musty or Moldy Smell is Coming from the Vents
If your HVAC system smells musty, it could indicate mold growth inside the ductwork, air handler, or evaporator coils — all of which can significantly worsen respiratory symptoms.
Mold thrives in humid environments, which is common in St. Louis, especially in spring and summer. Your HVAC system may be contributing to this problem if:
The condensate drain line is clogged
There’s excess moisture in your ductwork
Your home lacks proper dehumidification
A professional inspection can help detect and remove mold sources before they become a health hazard.
5. You Hear Unusual Noises or Your System Runs Constantly
An overworked or aging HVAC system may struggle to regulate temperature and humidity, creating ideal conditions for allergens to flourish. If your system runs nonstop or makes banging, rattling, or squealing sounds, it may not distribute air evenly or filter it effectively.
This can result in stale, poorly ventilated indoor air that traps allergens instead of removing them.
6. Your Humidity Levels Are Out of Balance
Humidity plays a major role in indoor air quality:
Too much moisture (>60%) can fuel mold, mildew, and dust mites.
Too little humidity (<30%) can dry out mucous membranes and worsen allergic reactions.
In St. Louis, homes often swing between humid summers and dry winters. Your HVAC system should help regulate indoor humidity, but if it doesn’t, consider a whole-home humidifier or dehumidifier.
7. You Haven’t Had Your Ducts Cleaned in Years (or Ever)
Over time, your ductwork can become a hidden hotspot for dust, mold, pollen, and even insect debris. Your system can blow those allergens back into your living spaces every time it runs.
If it’s been years (or decades) since your ducts were cleaned, you may benefit from a professional duct cleaning, especially if:
You have pets
You’ve recently renovated
You’ve moved into an older home
How to Allergy-Proof Your HVAC System
The good news? You don’t have to live with allergy-aggravating air. Here are simple yet powerful steps you can take:
Upgrade your air filter to at least MERV 11.
Schedule seasonal HVAC maintenance (spring and fall are ideal).
Install a whole-home air purifier or UV air scrubber.
Seal and clean your ductwork to eliminate hidden allergen sources.
Balance your humidity levels with a humidifier or dehumidifier.
Keep your home well-ventilated, especially bathrooms and kitchens.
Trust the Local Indoor Air Quality Experts in St. Louis
At Thomas Hoffmann Air Conditioning & Heating, we’ve helped hundreds of St. Louis families improve their home’s air quality and reduce allergy triggers, boosting energy efficiency and comfort. Whether you need a filter upgrade, duct cleaning, or a full IAQ solution, our licensed technicians are here to help.
Breathe Easier. Live Better.
Contact us today to schedule a free indoor air quality consultation. With local expertise you can trust, we can create a healthier, allergen-free home together.
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