4.7 
81 *The Angi rating for Heating And Air Conditioning Service companies in Herculaneum, MO is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Heating And Air Conditioning Service needs.
*The HomeAdvisor rating for Heating And Air Conditioning Service companies in Herculaneum, MO is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Heating And Air Conditioning Service needs.
Last update on July 19, 2026
Serving Herculaneum, MO and surrounding areas
Approved
In business since 2003
Free estimates
Emergency services offered
"A-ok! Dunn OneHour HVAC is always top notch!"
Serving Herculaneum, MO and surrounding areas
Approved
Super Service Award Winner
In business since 2017
Emergency services offered
Warranties offered
"Liberty did a fantastic job identifying and rectifying airflow problems with our existing Hvac system that was installed less than two years ago by another company. They were punctual, responsive and incredibly knowledgeable. I highly recommend them."
+10
Serving Herculaneum, MO and surrounding areas
Approved
In business since 2014
Free estimates
Emergency services offered
"Customer service was very helpful, tech was able to quickly diagnose the problem and solve it. We signed up for their preventative service HVAC."
Serving Herculaneum, MO and surrounding areas
Approved
In business since 1954
Free estimates
Emergency services offered
"I’ve used this company twice. My husband has a medical condition that is affected by heat. The first time the air conditioner wasn’t working they made every effort to assess the problem immediately when I explained the medical condition. At the time they corrected the problem I was advised the system was probably 20 years old and we may have to consider a new system soon. The second time I contacted Comfortable Carla’s was about 4-6 weeks later when the system wasn’t working again. This lead to a system replacement. I was provided with different options, my questions were answered and the installation was completed as quickly as possible, especially in view of my husband’s medical issue. The staff was was professional, efficient and kept me apprised all throughout the process. I highly recommend this company."
+1
Serving Herculaneum, MO and surrounding areas
Approved
In business since 1980
Free estimates
Emergency services offered
"The service tech was prompt, friendly, and helpful. They identified the issue with two fridges, and they recommended replacement or adjustment rather than costly unnecessary repairs."
Serving Herculaneum, MO and surrounding areas
Approved
In business since 1982
Emergency services offered
Warranties offered
Founded in 1982. Team members that are drug tested and background checked insuring that the people in your home are safe. We specialize in repairing and replacing residential heating and air conditioning systems. "Fixed Right or It's Free"\nTechs available Sat & Sun call for appointment.
Serving Herculaneum, MO and surrounding areas
Approved
In business since 2025
Emergency services offered
Credit card accepted
"Had a few issues with my HVAC. Austin was fantastic and fixed everything the same time. Was late"
Serving Herculaneum, MO and surrounding areas
Approved
Super Service Award Winner
In business since 2025
Free estimates
Credit card accepted
"Affordable, professional and quick! Would definitely use their services again."
Serving Herculaneum, MO and surrounding areas
Approved
In business since 2025
Free estimates
Emergency services offered
"They did a fabulous job in cleaning all the vents in the house. The entire crew was very professional and treated our home with care. Even our dog loved them! We highly recommend using them!"
+21
Serving Herculaneum, MO and surrounding areas
Approved
In business since 2003
Free estimates
Emergency services offered
"Had two HVAC systems in two story house, First cleaning of ductwork in 29 years. They started on the second floor, followed by the first and worked their way to the basement to finish. They did an overall good job, but left some dust bunnies even after final vacuum at end of the job. The work affected my sinuses after completion with the duct dust that was stirred up. Consider opening windows if possible to help minimize the dust that was stirred up, if anyone in house has allergies. For the price it was a good job."
+6
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