As St. Louis residents, we rely heavily on our air conditioning systems to keep us cool and comfortable during the sweltering summer months.
So when your AC starts blowing hot air instead of the refreshing coolness you expect, it can be frustrating and concerning. At Thomas Hoffmann Air Conditioning & Heating, we understand how disruptive this issue can be. Let’s explore why your AC might blow hot air and what you can do about it.
Thank you for the quick booking and reliable service. I never have to second-guess when my HVAC unit has an issue — your technicians are incredibly knowledgeable.
We recently contracted with Thomas Hoffman for our commercial HVAC maintenance. They were more reasonably priced than our previous contractor and they were prompt and professional on their first visit with us. We are more than satisfied with their service.
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!
Nick was fantastic from start to finish. He called ahead to give me an arrival window, which I really appreciated. It was 80+ degrees in my house and needed someone to come out today. I called two other places first and the earliest anyone could come out was tomorrow afternoon. The woman I spoke to on the phone said she could have someone out within the hour.
Once he was here, he took the time to actually show me what caused the leak rather than just describing it. That kind of transparency goes a long way.
He explained everything clearly, didn’t upsell anything, and was genuinely personable throughout the whole visit.
What stood out to me most was that he spoke directly to me and made sure I understood everything, not just the other person in the room. That’s rarer than it should be, and it made a real difference.
Highly recommend Thomas Hoffman Air Conditioning and Heating!
Nick was honest, communicative, and great at his job!
Response from the owner:Thank you, for your wonderful feedback! We're glad to hear that Nick provided such excellent service and took the time to ensure you understood everything. Your recommendation means a lot to us!
Nick came out and looked everything over to find the problem and while looking explained everything in detail and gave me great tips to keep system running smoothly. He was very professional and I know I will always call Hoffman whenever I need help because of his attitude and demeanor. Very happy with the service.
Response from the owner:Thank you, Ron, for your positive feedback! We're glad to hear that Nick provided you with detailed explanations and helpful tips. Your satisfaction means a lot to us, and we look forward to assisting you again in the future!
Professionally done , very friendly and easily let me understand the problem.
Response from the owner:Thank you, William! We're glad to hear that you had a positive experience with our team. Providing clear communication and friendly service is important to us. We appreciate your feedback!
I’ve been using “THOMAS Hoffmann Airconditioning and Heating LLC” for years now. We have a 30 +\- year old system that works perfectly for us. Although we’ve not had to use it yet, it is comforting to know they offer a 24 hour on call service. I really appreciate that the technicians don’t try to upsell us on anything. They’re a very professional, knowledgeable, and courteous, local-family owned and operated business. I’ve also found their pricing to be very fair and by”fair” I don’t mean “cheap” but reasonable… especially for the quality of service provided by THOMAS Hoffmann HVAC. I love supporting smaller family owned business and this one is top-notch! Thank you guys!
Response from the owner:Thank you so much for your continued support and kind words, Mari! We truly appreciate your loyalty and are glad to hear about your positive experiences with our services. We look forward to continuing to provide you with top-notch service in the future.
Excellent service from Nick! Friendly was super knowledgeable!
Response from the owner:Thank you, Margaret! We appreciate your kind words and will make sure to pass along your praise to Nick for his excellent service.
Our service technician arrived right on time and was professional, friendly, efficient and courteous. We couldn’t ask for more.
Response from the owner:Thank you for sharing your positive experience with our service technician! We appreciate your kind words and are glad to hear that you were satisfied with the service provided.
Nick was was great! He provided great service, explained everything, and was patient and kind.I definitely recommend using Hoffman!
Response from the owner:Thank you, Marilyn! We're glad to hear that Nick provided you with excellent service and made your experience enjoyable. We appreciate your recommendation!
The whole team was great, professional and friendly. Scheduling was easy and well organized, they had many options for different price points and financing options. Thank you!
Response from the owner:Thank you for the thoughtful review, Jasmine! We appreciate your support and continued business.
Love that it’s the same technician every time. Let’s me know what he found and any concerns he might have regarding our units. Great customer service.
Response from the owner:Thank you, Theresa! We're glad to hear you appreciate having the same technician and the communication about your units. Your feedback on our customer service means a lot to us!
From the phone to the completion of the job everyone is so polite and informative. I had Giovani as our representative and he was very informative and professional, and knew exactly what the problem was. Thanks so much.
Response from the owner:Thank you for the kind review, Frank! We appreciate you and your business.
Zach did an excellent job! Always courteous and friendly. We would highly recommend calling Thomas Hoffmann HVAC for any heating and cooling needs.
Response from the owner:Thank you, Allan! We're glad to hear that Zach provided excellent service and appreciate your recommendation for Thomas Hoffmann HVAC.
Was able to locate the problem right away and replace a switch and add Freon very nice job by this employee. I will recommend Thomas Hoffman for future references.
Response from the owner:Thank you, William! We're glad to hear that our team was able to quickly address the issue and that you had a positive experience with Thomas. Your recommendation means a lot to us!
I had Nick come out. He was awesome. Very knowledgeable, prompt and helpful. I will definitely recommend Thomas Hoffmann HVAC to others in need of HVAC support.
Response from the owner:Thank you, Jack! We're glad to hear that Nick provided you with excellent service. We appreciate your recommendation and look forward to assisting you and others in the future.
From our initial quote until the new furnace and AC were completed, everything was smooth and efficient. Zachary and Giovanni were excellent on-site, taking time to explain the installation as well as leaving the home clean.
Thank you Thomas Hoffmann team
Response from the owner:Thank you! We're glad to hear that the installation process was smooth and efficient. Zachary and Giovanni will be pleased to know their efforts made a positive impact. We appreciate your kind words about the team!
Update 4/6/26: Zach Sperling is such a pleasant and knowledgeable technician that I recommend him highly. Thomas Heating has been a wonderful company to work with in my maintenance plan. If you are looking for a reputable company, look no more.
This company is so responsive that I love them. They respond immediately, and I trust them to tell me what needs to be done. I haven’t been steered wrong yet. They are genuinely nice to work with and honest. I use their maintenance program which I highly recommend.
Response from the owner:Thank you for your kind words, we truly appreciate your trust in us and are glad to hear about your positive experience with our services.
So helpful! Straight into the point with no runaround or Negotiating up sells! Quick and efficient!
Response from the owner:Thank you for the great review, Julie! We appreciate your business and the support!
Top Reasons Your AC May Be Blowing Hot Air:
Thermostat Issues
Dirty Air Filter
Low Refrigerant Levels
Frozen Evaporator Coil
Compressor Problems
Outdoor Unit Issues
Leaky or Damaged Ductwork
Incorrectly Sized AC Unit
Let’s dive deeper into each of these issues:
Thermostat Issues
Before diving into more complex problems, always start with the simplest explanation. Check your thermostat to ensure it’s set to “cool” mode, and the temperature is lower than the current room temperature. Sometimes, the issue is as simple as an accidental switch to “heat” mode or a thermostat that needs new batteries.
Dirty Air Filter
A clogged air filter is one of the most common culprits behind an AC blowing hot air. When your filter is dirty, it restricts airflow, causing your system to work harder and potentially overheat. This can lead to warm air coming from your vents. We recommend checking and changing your air filter every 1-3 months, depending on usage and household factors like pets or allergies.
Low Refrigerant Levels
Refrigerant is the lifeblood of your AC system, responsible for absorbing heat from your home’s air. If your system is low on refrigerant, often due to a leak, it can’t effectively cool the air. This results in warm air blowing from your vents. If you suspect a refrigerant issue, contacting a professional HVAC technician is crucial, as handling refrigerant requires specialized training and equipment.
Signs of Low Refrigerant:
Warm air from vents
Hissing or bubbling sounds from the AC unit
Ice formation on refrigerant lines or evaporator coil
Higher than average energy bills
Frozen Evaporator Coil
Ironically, a frozen evaporator coil can cause your AC to blow hot air. This can happen due to restricted airflow (often from a dirty filter) or low refrigerant levels. When the coil freezes, it can’t effectively absorb heat from your home’s air. If you notice ice on your outdoor unit or indoor air handler, turn off your system and call for professional service.
Compressor Problems
The compressor is the heart of your AC system and is responsible for pressurizing and circulating the refrigerant. If it’s not working correctly, your system won’t be able to cool the air. Compressor issues can range from electrical problems to mechanical failures and typically require professional diagnosis and repair.
Outdoor Unit Issues
Your AC system consists of both indoor and outdoor components. If the outdoor unit is dirty, blocked by debris, or not receiving power, it can’t effectively release the heat absorbed from your home. This results in the system recirculating warm air. Ensure your outdoor unit has clear space around it and is free from leaves, grass clippings, and other debris.
Leaky or Damaged Ductwork
Sometimes, the problem isn’t with your AC unit but the ductwork that distributes the air. Leaks or damage in your ducts can allow hot attic air to mix with the cooled air, resulting in warm air from your vents. Professional duct inspection and sealing may be necessary to resolve this issue.
Incorrectly Sized AC Unit
If your AC system is too small for your home, it may struggle to cool the air effectively, especially on the hottest days. Conversely, an oversized unit might cool your home too quickly, leading to short cycling and poor humidity control. Both scenarios can result in inconsistent cooling and potentially warm air from your vents.
What Should You Do?
If your AC is blowing hot air, here are some steps you can take:
Check your thermostat settings and batteries.
Inspect and replace your air filter if it’s dirty.
Look for signs of freezing on your indoor or outdoor unit.
Ensure your outdoor unit is clean and unobstructed.
If these simple checks don’t resolve the issue, it’s time to call in the professionals.
Benefits of Professional AC Maintenance:
Improved energy efficiency
Extended system lifespan
Reduced risk of unexpected breakdowns
Better indoor air quality
Consistent cooling performance
At Thomas Hoffmann Air Conditioning & Heating, we have the expertise to diagnose and resolve various AC issues. Our team of certified technicians can quickly identify the root cause of your AC blowing hot air and provide practical solutions to get your system back to peak performance.
Remember, regular maintenance is vital to preventing many of these issues. Schedule annual tune-ups with our team to keep your AC system running efficiently and extend its lifespan.
Contact Us Today
Don’t suffer through the St. Louis heat with a malfunctioning AC. If your system is blowing hot air or experiencing other cooling issues, contact Thomas Hoffmann Air Conditioning & Heating today. We’re here to ensure your home stays relaxed and comfortable all summer.
