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TRUSTED BY O FALLON, MO HOMEOWNERS

  • Average homeowner rating star icon4.7
    Average homeowner rating
  • Verified reviews icon1.2k+
    Verified heating and air conditioning services reviews

Find Heating and air conditioning pros in O Fallon

Avatar for Fresh Air Heating & Cooling
Fresh Air Heating & Cooling
4.8(
277
)
Central A/C - InstallCentral A/C - Service or RepairElectric Furnace / Forced Air Heating System - Install+47 more

Serving O Fallon, MO and surrounding areas

Approved

In business since 1947

Free estimates

Emergency services offered

"Great Experience. I was concerned about the 22 yr age of our air conditioner able to keep working and wonder if a long wait time to get a product shipped like refrigerators last year, I called for a quote and within a week it was installed and working! Installers worked tirelessly until their work was done, clean and neat!"
Fresh Air Van
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+2

12 neighbors recently requested a quote
Recommended by92%of homeowners
Avatar for Liberty Heating & Cooling
Liberty Heating & Cooling
4.8(
46
)
Central A/C - InstallCentral A/C - Service or RepairBoiler or Radiator Heating System - Install or Replace+25 more

Serving O Fallon, MO and surrounding areas

Approved

Super Service Award Winner

In business since 2017

Emergency services offered

Warranties offered

"Liberty did a fantastic job identifying and rectifying airflow problems with our existing Hvac system that was installed less than two years ago by another company. They were punctual, responsive and incredibly knowledgeable. I highly recommend them."
A/C replacement
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+10

5 neighbors recently requested a quote
Recommended by93%of homeowners
Avatar for Hively Home Comfort LLC
Hively Home Comfort LLC
4.8(
47
)
Central A/C - Service or RepairElectric Furnace / Forced Air Heating System - RepairGas Furnace / Forced Air Heating System - Repair+2 more

Serving O Fallon, MO and surrounding areas

Approved

In business since 2017

Free estimates

Credit card accepted

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.

3 neighbors recently requested a quote
Recommended by65%of homeowners
Avatar for All American Appliance Service Inc
All American Appliance Service Inc
4.5(
531
)
Central A/C - Service or RepairThermostat - Repair or Reprogram

Serving O Fallon, MO and surrounding areas

Approved

In business since 1980

Free estimates

Emergency services offered

"Fantastic company that went above and beyond for me. They were punctual, professional and did a top notch repair job on my washer in a very timely manner. What set this company apart from other companies is that it’s locally owned, been in business 40 years and is run like an old school business (that’s hard to find these days). They offer unmatched customer service, superior work, and great prices. The company manager/owner took my order personally over the phone. I knew I was in competent hands and ones I could trust. I must mention something about our service technician (who in addition to the above mentioned) is the reason I plan to give this company my lifelong loyalty and business. His name is George (@city location) and honestly speaking, I don’t think I’ve come across a kinder more patient person who’s come to my home for any type of job. I must have wasted at least an hour of his extra time (inadvertently) due to a mixup I made with my credit card (100% my fault). This mistake(s) caused this sweet man to have to leave my home and come back to my door from his car THREE separate times. He had to then write out three separate service orders, voiding the first two. The temp was close to 100 F that day, and I’ll tell you, he couldn’t have been kinder or more patient about it. When I told him how sorry I was for taking time away from his other customers, he said, “You are my customer right now.” I was so impressed by this as well as the company and workmanship overall. Afterwards, I called and spoke with the company’s manager/owner, Boris, to explain what had happened. He also, was such a kind, personable and understanding individual who listened and thanked me repeatedly for my service. If you’re looking for a fantastic Appliance Repair Service, LOOK NO FURTHER than All - American Appliance Service Inc.!!"
Additional Photos
Response time2 days
4 neighbors recently requested a quote
Recommended by89%of homeowners
Avatar for AAA Home Services
AAA Home Services
4.9(
9
)
Central A/C - Service or Repair

Serving O Fallon, MO and surrounding areas

Approved

In business since 1970

Warranties offered

Small jobs welcome

"I highly recommend AAA home services. They installed a brand new HVAC system and the entire process was trouble free every step of the way. I have had them out to service the system twice a year and the scheduling to do so is easy and the service has been excellent. AAA home services has always communicated well and I have had them do exceptional plumbing work including the installation of a hot water heater. Thank you AAA home services."
AC units from American Standard
HVAC Installation
HVAC Installation
1 neighbors recently requested a quote
Avatar for Aire Serv of St. Louis
Aire Serv of St. Louis
5.0(
5
)
Central A/C - InstallGas Furnace / Forced Air Heating System - InstallAir Ducts & Vents - Clean+11 more

Serving O Fallon, MO and surrounding areas

Approved

In business since 2024

Free estimates

Emergency services offered

Looking for reliable HVAC service in St. Louis? Aire Serv of St. Louis is your local expert for residential and commercial heating and cooling. From emergency AC repair during humid Missouri summers to furnace maintenance before the winter chill, our professional technicians are available to keep your home comfortable. We pride ourselves on transparent, upfront pricing, no overtime charges, and the "Done Right Promise." Whether you need a system replacement, duct cleaning, or a routine tune-up in Fenton, Webster Groves, or Kirkwood, we are the team you can trust. Breathe easy with Aire Serv—your comfort is our top priority. Call us today to schedule your service!

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30 neighbors recently requested a quote
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Heating and Air Conditioning questions, answered by experts

No. HVAC, which stands for heating, ventilation, and air conditioning, includes all of the systems that work together to regulate a building’s temperature and humidity levels. In comparison, air conditioners only provide cooling. You can have an air conditioner as part of your HVAC system, but not all HVAC systems include air conditioners.

You can adjust uneven airflow in your home by adjusting the dampers on the vents. However, if the temperature feels consistent throughout the home, don’t worry too much about uneven airflow. Generally speaking, larger rooms should receive more airflow than smaller rooms, especially if they only have one vent.

Yes, you should turn off your AC if it’s leaking. Turning off the system prevents more condensation from leaking and reduces strain on the unit if a damaged internal component or lack of refrigerant is the cause. While this may temporarily stop the leak, water can continue to drip from a thawing coil even after the system is off. As soon as you notice a leak, turn off the unit and investigate the source or call a professional for an inspection.

Turn your system off when you're toasty or when you're out to prevent unnecessary wear. Using the timer on your thermostat so that it switches off when it reaches a certain temperature or turns on just before you get back from work is best. An annual maintenance contract can be helpful to ensure your system receives these important services at regular intervals.

They can, but it’s not as common. Window AC units are much smaller than whole-house systems and less likely to develop refrigerant leaks or similar issues. As a result, you will rarely need to add a new refrigerant, limiting overcharging problems. However, it’s still important to leave refrigerant management in the hands of professionals when window units need work.

The O Fallon, MO homeowners’ guide to heating and air conditioning services

From average costs to expert advice, get all the answers you need to get your job done.