The goal of most homeowners is to keep their energy bills down while staying cool and comfortable during the hottest summer days and nights.
When the weather is hot and humid, your air conditioner comes to the rescue and processes the outdoor air by cooling it down, getting rid of excess moisture, and making your indoor environment comfortable again. AC units are used all across America and are regarded as a needed feature, as the climate can go to extremes in many parts of the country.
Nowadays, there are plenty of modern AC units to choose from, and the extra features they pack are impressive, starting with the ability to use a smart thermostat and going through purifying functions or self-programming according to the weather predictions.
Whether you are using an old AC unit or you just bought a new model, you probably will be interested in keeping your energy bills down while still making sure that you will feel comfortable at home even in the hottest days.
A common “money-saving” tip that many people hear is to leave your AC running 24/7. Many people think this reduces the energy costs by keeping a steady flow and not allowing your home to get hot again. Is it a myth or a fact?
Thomas came over promptly I spoke with him about my concerns with my unit. Immediately got to work trouble shooting and resolved my issues. A+
Response from the owner:Thank you, James, for your kind words and for recognizing Thomas's promptness and dedication in resolving your concerns; we appreciate your feedback!
We have called Thomas Hoffmann many times and they are very prompt and very professional.
Response from the owner:Thank you, Vicki, for your kind words about Thomas Hoffmann's promptness and professionalism; we truly appreciate your feedback!
Super friendly, helpful, and quick to make the fix.
Response from the owner:Thank you, Jack! We're glad to hear you found our service friendly and efficient; your feedback means a lot to us!
Not a customer, but witnessed one of their technicians have an episode of road rage in Clayton. I would be concerned about letting them into my house/business.
We really trust Thomas Hoffman AC and Heating. Nick Hoffman has serviced our units several times now and he is professional, knowledgeable and very easy to work with. He comes on time, so we don’t have to schedule a long waiting period. We would highly recommend this company.
Response from the owner:Thank you, Greg, for your kind words and for trusting us with your AC and heating needs; we’re glad to hear that Nick has provided you with such great service.
We’ve been looking for a locally owned small HVAC dealer for a few years. And we found it with Thomas Hoffmann Air Conditioning & Heating. We love their service technicians. They come on time, they know what they are doing, they don’t upsell you on every appointment and they like working for Thomas Hoffmann. A happy employee makes for a happy customer.
Response from the owner:Thank you, Mary, for sharing your wonderful experience with us; we're glad to hear you appreciate our technicians and their commitment to great service!
I called on a Monday morning as air conditioning was blowing warm air. They were able to come to my house very early afternoon and fixed the problem. Would highly recommend and will use them again.
Response from the owner:Becky thank you so much for your great review. We appreciate your business and your kind words.
quick to arrive and fast service
Response from the owner:Thank you, Connie, for your kind words about our quick arrival and fast service; we appreciate your feedback!
Very good, pleased with service.
Response from the owner:Thank you! We're glad to hear you were pleased with our service and appreciate your kind words.
Excellent service from Nick!
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.
I am very pleased with the service provided.
, especially the quick response to my request . The technician came in themorning and had my cooling system repaired within an hour. Thank you !
Response from the owner:We're delighted we could promptly assist you on a Sunday morning and fix your cooling system efficiently. Thank you!
Here on time, worked fast. Always pleasant and great answering questions. Zach always does a great job.
Response from the owner:Thank you, Debra, for your kind words; we're glad to hear Zach made a positive impression and that you had a great experience with our team!
great job
Response from the owner:Thank you, Joe! We appreciate your kind words and the support from everyone involved.
Extremely quick response for appointment and did quick fix for our furnace and heat is working great !
Response from the owner:Thank you for your kind words! We're glad to hear our team was able to respond quickly and get your furnace working great. We appreciate your feedback!
They were timely, polite, professional and they saved us from too much sweating. In a field full of pompous and arrogant technicians, these guys take the time to explain what is wrong and how they are correcting it. Other folks just assume you are incompetent but these folks take the time to educate. Cannot recommend highly enough.
Response from the owner:Thank you for your kind words! We truly appreciate your feedback and are glad we could provide you with a positive experience.
Great service and arrived on time when promised.
Response from the owner:Thank you Wray, for your kind words! We're glad to hear you had a great experience and that everything was on time.
I would like to have a receipt for my payment which I did not receive. On a positive note he was very punctual very early actually he did his job and was very professional and I'm hoping and praying this took care of the issue thank you and I would not hesitate at this time to use your services
Response from the owner:Thank you, Mark, for your feedback and for highlighting the punctuality and professionalism of our team; we appreciate your support and will ensure you receive your receipt promptly.
Our experience with them was fantastic all the way through! Not only were they able to get to our business that day but the customer service from the phone call to the on-site service was professional and quick. We'll definitely be using Thomas Hoffmann Air Conditioning and Heating in the future.
Response from the owner:Thank you, Michelle, for your wonderful feedback! We're glad to hear about your fantastic experience and appreciate your kind words about our team's professionalism. We look forward to serving you again in the future!
Zachary was here on the dot at 8:00am. Thank for making me the first stop as promised. Very friendly too.
Response from the owner:Thank you for recognizing our professionalism and friendliness!
Competence and knowledge have been my experience.
Response from the owner:Thank you, Beth, for sharing your experience; it means a lot to us!
I couldn’t be happier with the service from Thomas Hoffmann Air-Conditioning! From the moment I called, the team was professional, responsive, and truly knowledgeable. Thomas personally made sure everything was handled with great attention to detail. The installation was smooth, efficient, and the quality of the work exceeded my expectations. It’s rare to find a company that is both skilled and genuinely cares about their customers. I highly recommend Thomas Hoffmann Air-Conditioning to anyone looking for honest, reliable, and top-notch service. They’ve definitely earned a loyal customer!
Response from the owner:Thank you, Rick, for your kind words and for recognizing our team's hard work; we're grateful for your support and thrilled to have earned your loyalty!
Amazing service from Thomas Hoffmann! They made space in their schedule to come out the next day to fix our air conditioner. They were on time, honest and fixed the problem on the spot. Thank you!
Response from the owner:Thank you, Ashley! We appreciate your kind words about our team's service – it's great to hear we could help you so quickly.
Excellent Service!
Response from the owner:Thank you, Lynda, for your kind words about our service; we truly appreciate your support!
Fast efficient service. Both of the gentlemen that came to my home were very help and informative not to mention polite. It’s difficult to get service advisers to appear at your home when scheduled most times they’re late or don’t show up at all. Not an issue with this team on time, clear diagnosis, quick repair. I would definitely use Thomas Hoffmann Air Conditioning again. I recommend them highly.
Response from the owner:Thank you, Anna, for your wonderful feedback! We're glad to hear that our team provided you with timely and helpful service, and we appreciate your high recommendation.
Tom was great. Super quick and easy! Serviced my unit in under 24 hours.
Response from the owner:Thank you, Olivia! We appreciate your kind words about Tom and are glad to hear your unit was serviced so quickly.
I have complete trust in Thomas Hoffman AC . I have had multiple
technicians who are always polite and knowledgeable.
Response from the owner:Thank you for your trust in our team, Henry! We appreciate your kind words about our technicians.
The OG brother, Thomas Hoffmann, his son Nick, who and the entire team are fantastic! They have my highest respect and recommendation!
Response from the owner:Thank you, Jane! We truly appreciate your kind words about Thomas, Nick, and the entire team; your support means a lot to us!
Fast response and great quality work.
Response from the owner:Thank you for your kind words about our fast response and quality work; we truly appreciate your support!
Very quick and efficient
Response from the owner:Thank you, for your kind words; we appreciate your recognition of our quick and efficient service!
He got my ac up in running in no time.
Response from the owner:Thank you, T! We're glad to hear that everything is running smoothly and appreciate your recognition of our team's effort.
Giovanni was amazing. Explained everything in detail.and really made sure my unit is operating at its best. Very happy with them.
Response from the owner:Thank you, William! We're glad to hear Giovanni provided such detailed service and ensured your unit is running smoothly.
Came out immediately after a time slot opened and fixed the AC issue.
Response from the owner:Thank you, James, for your kind words! We're glad we could address your AC issue promptly.
Outstanding in every respect.
Response from the owner:Thank you, Ordont, for your wonderful feedback; we're so glad to hear everything met your expectations!
Zachary was very knowledgeable and informative! Highly recommend!
Response from the owner:Thank you, Beth! We're so glad you found Zachary knowledgeable and informative—we appreciate your recommendation!
First visit for my maintenance program. Arrived on time. Very polite to talk to. They discussed what they did and everything was good. They were professional. I would recommend this company to everyone.
Response from the owner:We're delighted to hear about your positive first visit experience with us! Thank you for recommending our services.
They were quick and did an exce
llent job on a very hot day. Thank you
Response from the owner:Thank you for the 5-star rating, Tom!
Very knowledgeable. Very professional. Tom was very thorough and finally confirmed the issues in the system that no one else bothered to check.
Response from the owner:Thank you, David, for your kind words; it's great to hear that Tom's thoroughness made a difference in addressing the issues in the system. We look forward to working with you in the future!
Excellent Service. Thank you Zackery
Response from the owner:Thank you for your kind words, Buzz! It was a pleasure assisting you.
I’ve been using “THOMAS Hoffmann Airconditioning and Heating” 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.
Great customer service & experience for our HVAC System! They installed two UV lights and a dehumidifier. On time, great service, the new items work great - Great HVAC Service in St. Louis! Thank you!
Response from the owner:Thank you, Brandon, for your wonderful feedback! We're glad to hear that you had a great experience with your installations Your satisfaction is our priority!
Thank you Thomas Hoffman Air Conditioning for doing a great of repairing our HVAC system that was damaged during a power outage. You installed our new HVAC system late last year and promptly responded to our call for repair after a power surge impacted our subdivision.
Response from the owner:Thank you, Don, for your kind words! We're glad to hear that Thomas Hoffman Air Conditioning was able to assist you so quickly after the power surge and that you're satisfied with your new HVAC system. Your support means a lot to us!
Always great service!
Response from the owner:Thank you, Chris! We appreciate your kind words about our service and are glad to hear you had a great experience.

Should You Leave Your AC Unit on All Night?
The answer is: it depends. Essentially, it depends on the temperatures outside during the night. If the outdoor air gets cool enough for you to feel comfortable without the AC, then obviously there is no reason to turn it on.
However, if the outdoor air is too humid, your air conditioner can act as a dehumidifier. It is important to note that much of your comfort level will rely on the relative moisture in the indoor air. If the air outside is indeed too humid, then you might want to turn your AC on at night as well. Many air conditioning units today also have a dehumidifying function.
In most cases, you don’t really need your air conditioning unit to run the whole night, and it won’t necessarily make your energy bills lower. So what can you do to prevent your bills to skyrocket, while still feeling comfortable at night this summer?
Here are a few easy tips:
- Only using the fan function of your AC unit
- Installing ceiling fans in your bedroom
- Adjusting the cooling level and raising it up at night
Speak With a St. Louis HVAC Specialist
You need to consider other solutions too before deciding whether leaving your AC unit on for long periods of time is a good idea.
If you are interested in saving on energy costs because of unusually high energy bills, also have your AC unit checked for potential malfunctions. A faulty AC unit can make you try anything in order to keep the indoor air cool without spending a fortune on electricity. Hiring an HVAC expert to do an inspection is worth it. Give us a call today to schedule an appointment or discuss your cooling needs.