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Avatar for Fresh Air Heating & Cooling
Fresh Air Heating & Cooling
4.8(
277
)
Central A/C - InstallCentral A/C - Service or RepairCentral A/C - Install - For Business+3 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
Additional Photos
Additional Photos
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+2

12 neighbors recently requested a quote
Recommended by92%of homeowners
Avatar for Dunn Heating Air Conditioning and Plumbing
Dunn Heating Air Conditioning and Plumbing
4.7(
274
)
Central A/C - InstallCentral A/C - Service or RepairDuctless Mini-split A/C - Install or Replace

Serving O Fallon, MO and surrounding areas

Approved

In business since 2003

Free estimates

Emergency services offered

"I needed to replace my parents' 40 year old AC Condenser and coil, and replace it with something that worked with the new furnace my father got installed four years prior. They were able to do the work requested, and also offered to redo the furance installation as the previous company installed it right on the basement floor where any backup/water could possibly get into the system. They were very prompt and showed up on time/on schedule. They were very upfront about costs and pricing and there were no last-minute price changes or hidden fees, which I appreciate. Work was done well and they ensured that everything worked before leaving the job site. The gentlemen working were very professional and understanding. I highly recommend them for anyone looking to replace their HVAC or to correct work that was previously poorly done."
Additional Photos
Response time2 days
31 neighbors recently requested a quote
Recommended by89%of homeowners
Avatar for Aire Serv of St. Louis
Aire Serv of St. Louis
5.0(
5
)
Central A/C - InstallCentral A/C - Service or RepairAir Ducts & Vents - Clean+1 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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25 neighbors recently requested a quote
Avatar for Wise Men Heating and Cooling, LLC
Wise Men Heating and Cooling, LLC
5.0(
7
)
Central A/C - InstallCentral A/C - Install - For BusinessCentral A/C - Service or Repair+2 more

Serving O Fallon, MO and surrounding areas

Approved

In business since 2000

Free estimates

Emergency services offered

Wisemen Heating Cooling is a family owned company that focuses on tradition of craftsmanship and service. My father built a respected general contracting business that served our community with integrity and care. We are your best choice in St Louis and the surrounding communities for all your home improvement needs! We take great pride in every project we do and our customer's complete satisfaction is our top priority! Call us today for a free estimate!

Full furnace
Full furnace
Full furnace
Heating Cooling HVAC
HVAC

+2

Response time7 hrs
Response rate100%
5 neighbors recently requested a quote
Avatar for Schraer Heating and Air Conditioning
Schraer Heating and Air Conditioning
5.0(
8
)
Central A/C - InstallCentral A/C - Service or RepairDuctless Mini-split A/C - Install or Replace+3 more

Serving O Fallon, MO and surrounding areas

Approved

In business since 1946

Free estimates

Emergency services offered

"The 3 Mustache Pledge! Schraer Heating and Cooling deserves every bit of praise I can give! I called them about a worrisome noise coming from my system — one that I could only describe through a few rather vague and comical sound effects. Despite my less-than-technical explanation, their technician quickly understood exactly what I meant, found the issue, and had it fixed in no time. Their professionalism, responsiveness, and ability to solve the problem so efficiently (and with good humor!) made the whole experience stress-free. I’m so grateful for their excellent service and expertise. Highly recommend Schraer Heating and Cooling to anyone looking for honest, skilled, and friendly professionals! I will definitely keep my maintenance agreement in full force and effect!"
Airlift rooftop unit
Duct installation
Geothermal job
Crane lift a rooftop unit
Finalize duct on a new construction

+3

Response time1 day
43 neighbors recently requested a quote
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Showing 1-10 of 248
Air Conditioning questions, answered by experts

To make the most out of your AC, consider implementing the following best practices: 

  • Choose the right size AC for your home to ensure your unit runs as efficiently as possible.

  • Choose a window with shade, as direct sunlight can cause your AC unit to overheat. 

  • Clean or replace the filter at least every two months. 

  • Inspect the AC’s fan and straighten it if necessary. 

  • Discontinue use immediately if you suspect a malfunction, as running the AC while broken can lead to significant issues. 

  • Turn off (or adjust the temperature) when you leave the house.

While Freon is mostly odorless, a Freon leak will produce a faint chloroform-like smell. Some people find that Freon's odor has a subtle sweetness to it. Some telltale signs of a Freon leak beyond odor include ice crystals on your evaporator coil, bubbling sounds, and hissing noises.  

This depends on the extent of the freezing. Some ACs only need an hour or two to thaw out, but others may need a full day to completely unfreeze. Once you turn off the system to let it unfreeze, check it periodically to make sure the drain pan doesn’t overflow. When you turn the system back on, keep an eye on it to ensure it doesn’t start freezing again.

NATE (North American Technician Excellence) certification is not legally required for HVAC technicians in most areas, but hiring a professional with this certification is highly recommended. NATE-certified technicians demonstrated their expertise and proficiency in different types of HVAC systems, offering assurance of quality service. It's a voluntary certification, yet it indicates a commitment to professionalism and ongoing training. Choosing a NATE-certified technician often means you're working with someone who is up-to-date on industry standards and best practices, which can lead to better service, energy efficiency, and long-term cost savings.

AC drip pans last five to 20 years, depending on the material. Plastic AC drip pans last five to 10 years, while metal pans can last over 10 years. Plastic AC drip pans are vulnerable to cracking in response to temperature changes. Metal drip pans are prone to rusting over time, which can also lead to leaks.

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

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