Casto Technical Services would like to assure our customers that we will continue to provide quality service during the Coronavirus pandemic. We are taking every precaution necessary to keep our employees and customers safe and healthy. During this time, we are offering our hospital and medical center customers more service if needed. Please feel free to contact us with any questions or concerns.

From the Owner

Nate Casto began his career at Casto Technical in 1975. As president, Nate has managed the company through 40 of Casto’s 50+ years of business. While building the company, Nate worked in and first filled many of the roles in the organization. Beginning as a service technician helper, Nate worked in the parts warehouse, as service coordinator, and as account manager. As he grew the organization, Nate filled these roles and began managing the business.

Nate is very proud of the organization. Most importantly, Nate believes that the Casto team is a superior organization, that is continuing to grow and build a reputation for excellence in the industry. Nate will always testify that the success Casto Technical enjoys is due entirely to the work of highly qualified associates working as a team.

We Make Buildings
Work… Better!

Casto Technical Services, Inc. located in Charleston, West Virginia, has provided the area and parts of Ohio, Virginia, Maryland, Kentucky, and Pennsylvania with commercial HVAC services for over 50 years. 

We don’t just know buildings; we know building systems. From installation to service, Casto Tech understands the environment of your building and what it takes to keep it running smoothly to ensure the comfort of your employees and customers. 

We take pride in knowing that our experienced and highly trained team of technicians is committed to reducing your energy costs. By providing the right person equipped with the best technology and tools to get the job done, we are here to serve commercial, institutional, and industrial clients, 24-hours a day, 7-days a week.

For commercial heating and cooling services, including HVAC installation, preventative maintenance, emergency repairs, energy services, complete designs, building automation, and more, contact Casto Technical Services today to set up your appointment. Remember:


Where does your building energy usage rate?


Castro Tech Staff

HVAC Commercial Services

As the region’s longest-standing HVAC contractor, we deliver the best service available. Our trained, experienced techs are ready to keep your equipment running.


Energy & Intelligent Services

Whether your building needs precise temperature control or your goal is energy efficiency and conservation, Casto Technical Services can get the job done.


Building Automation Services

Building automation is key to efficiency and building optimization. Casto uses non-proprietary software to integrate any automation system seamlessly.

Engineered solution

Designed Solutions

Looking for a system for new construction, or is it time to upgrade your current HVAC system? Our experienced team is here to help.


5-star work. An incredible, professional company. Highly recommended!

Skyler Barnhart

Wonderful people to work with – highly recommend!

Ashley Willard


Phone: 800-232-2221


If you have an issue, you want to talk to someone that’s been there. We’re here to help; on the phone or on the site. Customers need answers, not more questions. Fill out the form and we’ll be right with you!