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TRUSTED BY O FALLON, IL HOMEOWNERS

  • Average homeowner rating star icon4.6
    Average homeowner rating
  • Verified reviews icon347
    Verified heating and air conditioning services reviews

Find Heating and air conditioning pros in O Fallon

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+11 more

Serving O Fallon, IL 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
21 neighbors recently requested a quote
Avatar for Healthy Home Pest Control & Services
Healthy Home Pest Control & Services
4.4(
385
)
Air Ducts & Vents - Clean

Serving O Fallon, IL and surrounding areas

Approved

In business since 2017

Free estimates

Emergency services offered

"Tim and Jeff were very fastidious in setting up, cleaning, and making sure the house was in good order when they left . We also had an Aeroseal treatment which followed with James and Connor. It did take some time to set up after the vents were cleaned and blown out, but the application of this polymer to close gaps in lthe galvinized steel ducts was remarkable."
New Trucks
Duct Cleaning Trailers
New Sign
Response time9 hrs
Response rate91%
492 neighbors recently requested a quote
Avatar for Vital Electric Heating and Cooling, LLC
Vital Electric Heating and Cooling, LLC
4.3(
19
)
Central A/C - InstallCentral A/C - Service or RepairDucts & Vents - Install or Replace+14 more

Serving O Fallon, IL and surrounding areas

Approved

In business since 2006

Emergency services offered

Small jobs welcome

"They were the only one that were able to come out on a Sunday. Found the problem and got our ac working during a heat advisory. Very satisfied with the results and will continue to use them again. Will recommend them to friends and family."
Full system install
Response time10 hrs
12 neighbors recently requested a quote
Recommended by87%of homeowners
Avatar for Mr. Handyman Metro East
Mr. Handyman Metro East
4.6(
196
)
Thermostat - Install or ReplaceThermostat - Repair or Reprogram

Serving O Fallon, IL and surrounding areas

Approved

In business since 2000

Warranties offered

Small jobs welcome

"Bob came out and provided an estimate which included options for completing the work. Once the work was scheduled he arrived on time and courteous, as usual. New security light of our choosing was installed in our backyard and a GFI outlet were installed in the garage in under an hour. We have used Mr. Handyman Metro East for several projects at our home and continue to use them because of their professionalism, value and customer focus."
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+5

Response time1 day
Response rate92%
Recommended by95%of homeowners
Avatar for Morrison Plumbing, Heating, Air & Electrical Services
Morrison Plumbing, Heating, Air & Electrical Services
5.0(
5
)
Central A/C - InstallCentral A/C - Service or RepairDuctless Mini-split A/C - Install or Replace+5 more

Serving O Fallon, IL and surrounding areas

Approved

In business since 1990

Free estimates

Emergency services offered

Your home's plumbing, HVAC, and electrical systems keep your family comfortable and safe. When something goes wrong or you're ready to upgrade, Morrison Plumbing, Heating, Air & Electrical is the Metro East team that delivers same-day service, upfront pricing, and work you can count on.\n\nWe serve Caseyville and surrounding communities through hot, humid summers and cold Illinois winters. Our technicians are licensed, insured, and trained to repair and install heating, cooling, plumbing, and electrical systems so your home stays reliable year-round.

HVAC Maintenance
Air Conditioner
Heating Repair
AC Service
HVAC Repair

+6

60 neighbors recently requested a quote
Avatar for Local Air Duct Pros
Local Air Duct Pros
4.5(
15
)
Air Ducts & Vents - Clean

Serving O Fallon, IL and surrounding areas

Approved

Super Service Award Winner

In business since 2025

Free estimates

Credit card accepted

"Thank you for your trust! At Local Air Duct Pros we specialize in professional air duct cleaning, dryer vent cleaning, chimney sweep, and attic insulation. Our licensed and insured team is committed to providing top-quality service at fair prices. We appreciate your support and look forward to serving you again!"
Response time7 hrs
Response rate97%
29 neighbors recently requested a quote
Tiger Plumbing, Heating, Air Conditioning, & Electrical Services
3.4(
353
)
Central A/C - Service or RepairGas Furnace / Forced Air Heating System - RepairHeat Pump - Repair or Service

Serving O Fallon, IL and surrounding areas

Approved (Corporate)

In business since 1993

Free estimates

Emergency services offered

"My technician Keith was great. Friendly and super informative. Also too a quick look at the entire drainage system and gave my an idea of where problems will pop up the future without preventative measures (my home was built in the 50s and while the previous owners took really good care of the house nothing has been gutted and replaced yet)."
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+5

188 neighbors recently requested a quote
Recommended by74%of homeowners
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Showing 1-10 of 209
Heating and Air Conditioning questions, answered by experts

For the most part, you should leave your AC fan in “auto” mode so that it only runs during a heating or cooling cycle. Keeping it in this position uses less energy, which equals lower utility bills. However, there are some situations where it’s better to leave your AC fan on, including if you have allergies or there are lots of people in your home.

No, it's not advisable to only replace the outside AC unit connected to your system. AC units are designed to work as a cohesive system, and older units work differently than newer units. Therefore, replacing only one component can lead to incompatibilities that affect the system’s performance. Replacing one component can void your warranty, costing you money for repairs.

If both your furnace and AC unit are more than a decade old, it may be a good idea to replace both of them. However, your furnace can last up to three decades, and your air conditioner can typically last up to 15 years, so consulting with a pro before deciding to replace both of them is best. If it’s before that time limit for each, you can fix many problems with repairs or just replace one.

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.

You should plan to change your AC unit's filter every one to three months, depending on the manufacturer's recommendations. You should also clean the coils at least once per year, but if you have pets or someone in your household has allergies, you might need to clean them more often. Fortunately, many pros will clean the coils and change the filter for you during an inspection, which you should schedule once or twice per year.

The O Fallon, IL 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.