Hours: We are open 24/7

2183 West Terra Lane, O'fallon, MO 63366

(314) 513-0385

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AC Installation Services for O Fallon, MO & surrounding communities

If you are considering first-time air conditioning installation, or thinking of updating your comfort, prepare to be amazed with innovations in technology.  Today’s sleek-looking, streamlined cooling equipment features digital displays, timers, intelligent controls with WiFi compatibility, zoning, energy tracking, maintenance alerts, filter change notifications, customization of temperature, air quality, fan speed, ventilation, and much more.  Taking advantage of adaptable-speed technology, these systems automatically adjust capacity to optimize efficiency and maintain temperatures within a half degree of your thermostat setting.  Virtually noiseless, simple to maintain, and protected by outstanding warranties, a state-of-the-art air conditioner will greatly improve the health, cleanliness, and comfort of your everyday life.  And when you partner leading-edge equipment with precise sizing and perfect installation from Reliable Heating and Cooling, you’ll enjoy maximum benefits from your investment.

Air Conditioning Installation & Replacement Services

ENERGY STAR rated models, with SEER ratings above 20, can save you up to 30% on cooling bills every year.  By qualifying as a Carrier Factory Authorized Dealer, Reliable Heating and Cooling offers a range of options within the Comfort, Performance, and Infinity Series, achieving up to 21.00 SEER and sound levels down to 56 decibels.  Along with traditional cooling systems, we also specialize in ductless units and heat pumps.  All of these systems represent the epitome of home comfort, and deliver the monthly and lifetime cost-savings that quickly recover the investment.  Know that the team from Reliable Heating and Cooling will work with you and provide knowledgeable recommendations, meeting your specific requirements with the perfect solution.  Each and every member of our installation staff is NATE-certified, having completed intensive factory training and verified their proficiency through industry-recognized exams.

Call Reliable Heating and Cooling for air conditioning installations you can trust for years to come!
O Fallon, Saint Peters, Lake Saint Louis, Wentzville, and Saint Charles, MO

At Reliable Heating and Cooling, we do more than answer your hopes for corner-to-corner comfort.  We make the installation process convenient, simple, and stress-free.  Established in 1972, we put our experience to work for you, overseeing every detail of the project and ensuring that your expectations for budget, time of completion, and rewarding results are met.  We’ll familiarize you with exciting features, and explain proper operation of your new system.  We’ll also make sure the scorching summer heat in O Fallon, MO & surrounding communities is no longer a factor when it comes to the enjoyment of your home.  And once you’re perfectly cool, we’d be happy to set up a maintenance plan to protect the ongoing performance of equipment.  For air conditioning installation or upgrades across O Fallon, Saint Peters, Lake Saint Louis, Wentzville, and Saint Charles, MO, count on Reliable Heating and Cooling.  We’re the name you can trust.

Central AC Installation O Fallon, MO | AC Installation Saint Peters, MO | Air Conditioner Installation Lake Saint Louis, MO

Air Conditioner Installation, Air Conditioning Installation, AC Installation & HVAC Installation O Fallon, MO, Saint Peters, MO, Lake Saint Louis, MO, Wentzville, MO & Saint Charles, MO

Central AC Installation O Fallon, MO | Air Conditioner Installation Saint Peters, MO | AC System Installation Lake Saint Louis, MO

Cooling System InstallationAir Conditioner InstallationCentral AC InstallationAC System Installation ∴ Wentzville, MO ∴ Saint Peters, MO ∴ O Fallon, MO

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Customer Reviews
What our customers are saying

Have been with them for more than 10 years. They provide exceptional service…from the time they call to remind you about setting an appointment to the actual service day. Derek (and all their other technicians) are knowledgeable, professional, prompt, and open to listening to questions and pay attention to details. Never had a problem with anything. Thank you for a job well done. Good pricing.

Seema Chouhan

Reliable has installed and maintained our last 2 furnaces and AC. Our experience with them has been great. Just yesterday we had an issue with our AC. I talked to Marty and he said he’d have someone out the next day. They even were able to accommodate us with an afternoon call. Derrick arrived promptly on time and had us up and going again in 15 minutes (bad capacitor on the condenser unit fan motor). With the prediction of high 90 temps, we were so thankful to have AC working again.

Keith Scherer

We had a emergency water leak problem with our AC unit in the basement of our recently purchased condo. Called Reliable and Derrick was there within a couple of hours. He was polite, knowledgeable, and friendly. Derrick quickly found the problem and repaired it. He also checked the system overall, pointed our some concerns and answered all my questions. I can’t say enough about how satisfied we were with Derrick and Reliable Heating & Cooling! We would definitely recommend them!!! Thanks again!!!!

Terry Mills

Had a small gas leak for a property I was helping a friend sell and we found out late last night. We reached out to Reliable H&C and Derrick was over first thing in the morning. He was friendly, professional and knowledgeable. He answered my questions with a smile. Derrick was a rock star. Will absolutely call him again. Bravo

Connor Kapp

I had a system malfunction on Sunday evening December 12, 2022 on my Carrier Infinity ICS purchased in 2008.I am a first time caller to Reliable. Marty called me back and had his Tech dispatched at 8 AM the next day. The unit had failed and was dangerous to use. He had a new system by the next morning. They installed it and I was completely satisfied with their service and response time. I overwhelmingly recommend Reliable and will be using them from now on.


We have used Reliable Heating and cooling for all of our heating and cooling needs. We needed some water heater work and Ralph came out and took care of it right away. Ralph was very professional and knowledgeable. He got the job done very quickly and everything is working great! I always recommend Reliable to family and friends. They truly are Reliable!

Chris Lopez

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