Get matched with top heating and air conditioning pros in O Fallon, MO

O Fallon homeowners rate heating and air conditioning pros in our network

4.7

(1.2k reviews)

Top-rated heating and air conditioning pros.

Need a pro for your heating and air conditioning service project in O Fallon, MO?

Select your specific project to find the pro for you.

Find Heating and air conditioning pros in O Fallon

Avatar for Fresh Air Heating & Cooling
Fresh Air Heating & Cooling
4.8(
277
)

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
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+2

8 neighbors recently requested a quote
Recommended by92%of homeowners
Avatar for Anton's Plumbing, Heating/Cooling & Energy Experts
Anton's Plumbing, Heating/Cooling & Energy Experts
4.7(
513
)

Serving O Fallon, MO and surrounding areas

Approved (Corporate)

Super Service Award Winner

In business since 1979

Free estimates

Emergency services offered

"I always recommend Anton's to family and friends who need HVAC services. Their prices are reasonable, and their service is top notch! All of their technicians are very professional and considerate and they don't try to sell you things you don't need. Ronan just came out this morning to do our annual A/C inspection. The service was excellent as always. He took the time to explain everything and made recommendations. I never felt pressured, and I trust this company to take care of my HVAC needs. They've got a customer for life!"
Additional Photos
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+18

Response time1 day
Response rate86%
16 neighbors recently requested a quote
Avatar for Liberty Heating & Cooling
Liberty Heating & Cooling
4.8(
46
)

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
Additional Photos
Additional Photos
Additional Photos
Additional Photos

+10

6 neighbors recently requested a quote
Recommended by93%of homeowners
Avatar for Hosack Plumbing Heating & Cooling
Hosack Plumbing Heating & Cooling
4.8(
344
)

Serving O Fallon, MO and surrounding areas

Approved

In business since 2009

Warranties offered

Credit card accepted

"Awesom. Highly recommend Glen. We bought new refrigerator and needed new updated waterline installed. Since we had plumber in house wanted to update things we knew we needed done eventually."
.
.
.
.
.

+2

Response time6 days
10 neighbors recently requested a quote
Recommended by93%of homeowners
Avatar for AAA Home Services
AAA Home Services
4.9(
9
)

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
Avatar for Anton's Plumbing, Heating/Cooling Energy Experts
Anton's Plumbing, Heating/Cooling Energy Experts
4.6(
81
)

Serving O Fallon, MO and surrounding areas

Approved

In business since 2000

Free estimates

Emergency services offered

"Both the estimator Kevin the two installers who visited my home were very professional and kind. They answered all my questions and provided a very reasonable price for the installation of the attic insulation. I feel I was very informed on the federal rebate that was available for this installation, as well as on the recommendations of quantity of insulation I needed per residential standards and codes. I would recommend Anton and will use them in the future for my HVAC needs!"
Response time6 hrs
Recommended by95%of homeowners
Avatar for Aire Serv of St. Louis
Aire Serv of St. Louis
5.0(
5
)

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!

Logo
27 neighbors recently requested a quote
...
Showing 1-10 of 374
Heating and Air Conditioning questions, answered by experts

Dry mode positively impacts indoor air quality by reducing excess moisture, which stops the growth of mold and mildew. By maintaining optimal humidity levels, dry mode creates a less hospitable environment for allergens and airborne pathogens, improving overall air quality. However, it's essential to ensure proper ventilation to prevent stale air accumulation.

If you’re looking for a portable, budget-friendly cooling solution that doesn’t require any venting or installation, a ventless AC system is a good option. Similarly, this is a great choice if you’re renting an apartment or home and aren’t allowed to make large, structural changes like installing comprehensive HVAC, or you’re in a shared space and only need to cool your own room.

When your HVAC system is loud, a few different causes are possible. If you have loose connections or bolts in the hardware, they can rattle as the system runs and vibrates. If you have an extremely dirty furnace filter, it could cause the system to generate noise. More commonly, an excessively loud HVAC system indicates a malfunction in the system. You may have a blower motor that is close to failing or a compressor that is breaking down. These issues require an immediate inspection.

While 72 degrees is a comfortable setting for many people, it’s likely not the most efficient temperature setting for your air conditioning unit. By pushing the temperature up to 75 or 78 degrees, you stand to save money on your energy bill. That said, these temperatures may be too warm to be comfortable for some people and are definitely too warm for most people to sleep comfortably.

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.

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.