Stay Cool Climate Control

Precision Mini-Split Installation & Replacement

When uneven temperatures, remodels, or lack of ductwork make traditional HVAC impractical, ductless mini-split systems offer a refined solution tailored to your home’s unique layout. These systems bring zone-by-zone comfort, quiet operation, and improved efficiency—perfect for additions, older homes, or spaces without existing ducts. Stay Cool Climate Control specializes in mini-split installation and replacement services in O’Fallon, MO, and the Greater St. Charles County area, offering modern ductless HVAC that meets diverse needs. Our certified technicians provide custom system selection, strategic placement, and expert setup. 

With our tailored approach, you’ll enjoy efficient, personalized comfort that adapts to your lifestyle. Call today to schedule your mini-split installation and upgrade your home’s comfort with smart, efficient cooling.

mini-split installation on the wall

What Is a Ductless Mini-Split?

A ductless mini split system is a highly efficient heating and cooling solution that doesn’t require traditional ductwork. Instead, it uses an outdoor condenser unit connected to one or more indoor air handlers, which deliver conditioned air directly into different zones of your home. This setup provides precise temperature control, quiet operation, and improved efficiency compared to central HVAC systems.

Because ductless mini splits can be installed in individual rooms or across multiple zones, they’re ideal for additions, older homes without ducts, or areas that never seem comfortable. Homeowners looking for greater customization may also explore our zoning systems, which work hand in hand with ductless solutions to maximize comfort and efficiency. With professional ductless mini split installation, you’ll enjoy targeted comfort, lower energy costs, and greater flexibility in managing your indoor climate.

Our Specialized Ductless Mini Split Installation Services

Every home has its own comfort challenges, and ductless mini splits are designed to solve them with precision. Stay Cool Climate Control offers ductless mini split installation and replacement services that adapt to the unique spaces in your home while delivering efficiency and reliability. From replacing outdated systems to installing new units in additions, older homes, or rooms without ductwork, our process focuses on creating long-lasting comfort. With expert guidance, professional craftsmanship, and a dedication to energy savings, we make upgrading to ductless simple and rewarding.

Custom System Design

Our team begins with a detailed assessment of your home to determine the best layout for your new ductless system. We match indoor air handlers and outdoor units to your unique needs, ensuring balanced airflow and consistent comfort. By tailoring your system, we maximize both performance and energy savings. A custom approach guarantees your ductless mini split delivers comfort exactly where you need it.

  • Systems designed around your home’s layout
  • Recommendations that balance efficiency and comfort
  • Guidance on single-zone or multi-zone setups

Professional Installation

Every ductless mini split installation is performed with precision and care. We carefully position each air handler for optimal airflow, run refrigerant lines with minimal disruption, and ensure all electrical connections meet safety standards. Professional installation improves system efficiency and extends the lifespan of your unit. With Stay Cool Climate Control, you can trust your investment is set up for long-term success.

System Replacement

If your current ductless system is no longer meeting your needs, our mini split replacement services provide a smooth upgrade. We remove your old system safely and replace it with a modern, energy-efficient model designed to perform better and last longer. Replacement often means lower energy bills, improved comfort, and fewer service calls. Our team ensures the transition is quick, efficient, and hassle-free.

  • Improved efficiency with new technology
  • Lower monthly energy costs
  • Reliable performance through every season

Performance Testing & Calibration

After installation or replacement, we perform detailed testing to confirm your system is operating at peak performance. This includes checking airflow, refrigerant levels, thermostat accuracy, and zone functionality. We also walk you through system controls so you can take full advantage of your ductless system’s features. Proper calibration guarantees efficiency, comfort, and confidence in your new investment.

Schedule Your AC Maintenance With Us Today!

Homeowners Choose Us: Here’s Why

Installing a ductless mini split is about creating a system that works seamlessly with your home. At Stay Cool Climate Control, homeowners in O’Fallon, MO, and the Greater St. Charles County area count on us for thoughtful planning, careful installation, and a service experience that prioritizes their comfort from start to finish. Here’s what sets us apart:

  • Detailed Planning: We map out every installation step to minimize disruption and maximize system efficiency.
  • Long-Term Focus: Our goal isn’t just to get your mini split running today — we set it up to deliver comfort for years.
  • Honest Recommendations: We present clear options so you can choose the system that best fits your home and budget.
  • Clean Finish: Every project is completed with attention to detail, from hidden line runs to tidy workspaces.
  • Local Commitment: As a family-owned company, we take pride in serving neighbors with dependable solutions and lasting results.

Ready for Ductless Mini Split Installation That Fits Your Home?

Stay Cool Climate Control delivers professional ductless mini split installation services in O’Fallon and the Greater St. Charles County area, designed to bring personalized comfort and energy savings to every room. From new system setups to seamless replacements, our team ensures your ductless system is installed with precision and care. Take the next step toward efficient, customized heating and cooling—call today to schedule your ductless mini split installation and start enjoying comfort on your terms.

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Testimonials

Hear from Our Satisfied Customers

Travis and Jacob and the other tecnicians were polite, and knowledgeable. They explained what they were doing. I now have a working furnace. They came in a timely manner.
Kathy Gregory
6 days ago
Travis and Jacob and the other tecnicians were polite, and knowledgeable. They explained what they were doing. I now have a working furnace. They came in a timely manner.
Kathy Gregory
1 week ago
Installers were very noticeable about the installation.explain in detail about My New unit I'm very pleased with My New unit
Julius James
1 week ago
NEW - update! 02/10/2026 : Dalton came out and was on time, courteous, and very well knowledgeable about my issue. He prescribed the right maintenance for my unique situation and made it simple to decide next steps. In & out! Also want to shout out Cindy for her great customer service and promotion of Stay Cool’s $79 furnace special right now! No pushy sales just quality maintenance and support from a great team of experts! Would highly recommend! ————————————— (Past experience) Jeremy & Nate were both professional and very informative of options I have for Replacement smart thermostat in addition to overall, maintenance tips. They had a pleasant, friendly nature and I would recommend them to neighbors and friends. I appreciated the ease of scheduling and the follow-up call from the office prior to the techs’ arrival too. Definitely a company I will keep in my pocket for future HVAC services.
Royelle Robertson
2 weeks ago
Travis , the technician, came out in very polite and professional and identified 2 problems I was experiencing with my furnace. The last few days have been very chilly. He stated what was needed and the price it would involve. With recommendations to plan on if other problems arise. He had to gather equipment needed to get the repair done he was quick and fastidious in his service and informed me when it was completed. Was very happy with the results. My furnace is running again and I’m warming back up. Thank you Stay Cool HVAC for you service.
Ethel Norfort
2 weeks ago
Brandon and the other guy were great! Quick install, reasonable pricing, and went over everything done. Definitely recommend.
John Jacobi
2 weeks ago
Jake and Trey were fantastic. Highly skilled and efficient and super nice dudes. We have used Stay Cool multiple times now including a furnace install. Their quote was spot on, they showed up when they said they would. Great experience. Travis was also super helpful in navigating a new furnace. We will be using them again when our other furnace finally dies. Thank you!
Aaron Bennet
2 weeks ago
Excellent job and detail replacing my HVAC. They treated me like family from pricing to installation and service.
Daniel Rosenthal
2 weeks ago
Dalton was amazing, couldn't ask for a better tech!
Keith Nemnich
3 weeks ago
Dalton was amazing!!!
Christina Nemnich
3 weeks ago
Travis was great! He not only worked quickly, but talked me through everything he was doing, gave maintenance tips and made sure I knew everything I needed to know before he left! He was friendly, prompt, and so helpful! I would absolutely recommend StayCool for any HVAC needs!
Jenna Whitmore
3 weeks ago
Always a great service from these guys. Jacob was out and went through my furnace and cleaned everything up. Very professional and easy to talk to. I’ve had them servicing my hvac for about 6 years now and they have always been able to make things work or work better.
Bailey Dickherber
3 weeks ago
On Jan 16, 2026 I called Stay Cool Climate Control to get a quote on replacing our old HVAC because the furnace was showing signs of imminent failure. I called the office in the morning, and Jeremy was able to come that afternoon. Jeremy looked at the old system and offered us multiple replacement choices. A few days later, after checking with 2 other companies, we concluded that Stay Cool was the best choice for us in terms of cost, efficiency, and equipment quality. We are not disappointed. Installation was scheduled for the following Tuesday. Brandon, Dalton, and Trey arrived on time early that morning, and after seeing the old system began removing it. Even though the outside temperature was in the teens and there was snow on the ground they worked tirelessly all day. By late that afternoon we had a new, highly efficient HVAC system up and running. Our thanks also go to Carter, who has answered many questions and was able to make the quick schedule possible.
Larry Pangborn
3 weeks ago
Very professional, fixed fast, highly recommend.
Scott Zoellner
3 weeks ago
HIGHLY Recommend. Our furnace quit right as a winter storm rolled in, and they sent someone out within an hour! Dalton figured out our issue and got our unit to work for just a bit longer until our replacement could be scheduled. Jake and Skylar handled our replacement. The office will send names and pictures of who is coming to your home, which made me feel very safe. Every person we encountered on the phone or in person was professional, friendly, and knew what they were doing. Pricing was fair and transparent, and they helped us get financing. Never felt rushed or pressured. A+ communication.
Lindsey Vazquez
3 weeks ago
On time arrival to service my furnace for the winter. Travis was very courteous. He carefully reviewed his findings and answered all of my questions. As a realtor and homeowner, I strongly suggest that your HVAC system be checked, serviced and cleaned twice yearly. Use a professional like Stay Cool Climate Control.
Mike Bronowicz
4 weeks ago
Brandon and Trey were awesome!!!
Anne Seiler
1 month ago
Jacob A was friendly and knowledgeable! Highly recommend this family owned company! Thank you, Tim & Cheri Dickherber/ Missouri Irrigation
Cheri Dickherber
1 month ago

    Schedule Your Service with Stay Cool Climate Control

    Don’t hesitate to reach out to us for the comprehensive solutions you need. We are happy to discuss any concerns you may have and will provide the honest, professional advice you need to help you make the best decision for your home. Contact us today to schedule a free second opinion, request an estimate, or book an immediate appointment for heating and air conditioning services in O’Fallon, Missouri.