About Us
Get to Know Us
Since 2000, Thermosystems has grown from a small group of innovators into a dynamic team spanning five specialized departments. We provide custom HVAC solutions across parts, service, equipment, building controls, and more. Today, we proudly partner with over 25 leading HVAC manufacturers who share our commitment to performance and innovation.
Our headquarters in Elmhurst, Illinois is supported by our fully stocked Romeoville parts warehouse and training facility, as well as offices in Chicago’s West Loop, Peoria, and a Daikin service office in Iowa. These locations allow us to serve commercial HVAC customers across Chicagoland, Central Illinois, Northern Indiana, and Iowa with localized support and deep technical expertise.
Why Choose Us?
- Proud members of Local Union 597
- HVAC expertise across service, controls, equipment, and parts
- Industry-leading parts division
- Trusted representative for 25+ industry-leading manufacturers
- Committed to customer success and long-term partnership
- Committed to employee career training and growth
- Strategic locations for fast, localized support

Embracing Sustainability
Sustainability in HVAC is vital for decarbonization, enhanced energy efficiency, and ensuring long-term cost savings. We actively support sustainability in 3 core areas:
Social
- OSHA 30 certified technicians
- We help our customers make informed purchasing decisions through exceptional customer support and educational content
- We support our community through partnerships with local organizations
- We actively engage with industry organizations to drive conversation and innovation in HVAC
Economic
- We recommend equipment solutions that promote decreased operational costs
- We help customers access efficiency savings such as ComEd and Nicor rebates
- We have consistent and robust stocked warehouse inventory, ensuring faster access to parts and shorter project timelines
Environmental
- Our staff includes individuals with LEED certifications, bringing sustainable expertise to our customers
- We prioritize customer energy usage, assuring that the building and equipment are functioning as designed
- We strive to create partnerships with manufacturers who prioritize making eco-responsible decisions