Air Conditioning Companies in O Fallon, MO

Comprehensive list of commercial and residential air conditioning companies in O Fallon, MO offering installation, repair and maintenance services.

Business Listings

Grand Oaks grew from one man and a pickup truck in 1990 to a complete-service firm with professional technicians and installers, a fleet of trucks stocked with necessary tools and parts, an office that uses a GPS dispatch system and a staff of the nicest people you would want to suit. We can service your castle, whether it's a 25,000 square foot home with a swimming pool or a small trailer.


Would you like to have your Air-Conditioner and Furnace running at peak performance every time they are used? We thought so, that is why we began providing what we call a QSA Quality Service Agreement. Twice a year an appointment is made and we'll arrive at your home to clean and adjust your Air-Conditioner and Furnace.


The owner, Rick Nipper, has been in the HVAC trade since 1976. We serve only the Lake of St. Louis, O'Fallon and St. Peters areas. We appreciate our clients and realize that word of mouth is the finest form of advertizing. O'Fallon Air supplies quality service at a very affordable price. No 2nd diagnostic charge if your system should break down within thirty days of our 1st visit.



Check with Sauer Heating and Cooling for savings, rebates, seasonal promotions, and financing. Let Sauer Heating and Cooling aid you select the finest Heating and Air Conditioning system for your home. Choose from a comprehensive line of home comfort products from gas- and oil-fired furnaces to air conditioning systems to heat pumps and air handlers every unit backed by complete buyer protection for


Cisco Heating & Air Conditioning was began in 1979 by Bob & Dorothy Cissell who, after three decades of working for other firms in the field, decided to strike out on their own to supply the people of St. Charles with knowledge and knowledge pertaining to the HVAC industry.


Warmth, comfort and reliability during the cold winter months? Comfortable stable cool air conditioning when the weather is hot and sticky? A provider with a excellent reputation? A provider who will fix problems promptly? A heating & cooling system that is environmentally friendly? A supplier that will tailor fit the system to your specific requirements?

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The corporate mission of Commercial Coils is to supply clients around the world in the HVAC, Industrial, and Laundry/Dry-cleaning markets with best quality heat transfer products that consistently meet or exceed their expectations. Our philosophy of individual service and timely performance has insured our success as an industry leader over the past quarter of a century.


RJI Welcomes Chris Swallow to the TEAM! Chris Swallow has joined RJI as a Sales Engineer. Chris previously worked for Boeing Company and he is a graduate from University of Missouri-Rolla S&T. The VS series is available in four cabinet sizes ranging in airflow capacity from 2,500 scfm to 15,000 scfm and can be used to precondition outdoor air going to other conventional air handling systems or as an