Daikin Applied Service is a commercial HVAC provider based in Chicago, IL, offering a wide range of heating, ventilation, and air conditioning services. They specialize in installation, repair, and maintenance of AC units, furnaces, heat pumps, and indoor air quality systems for various commercial and industrial facilities. Daikin Applied Service uses advanced technology and a proprietary asset management system to help clients manage HVAC equipment efficiently and plan for future capital expenses. Their services support energy-saving solutions and operational cost control, catering to buildings such as high-rises, hotels, data centers, schools, and hospitals.

Y-Tech Heating & Air Conditioning is a licensed HVAC contractor serving Chicago, IL, and the surrounding communities. They provide a range of services including installation, repair, and maintenance of air conditioners, furnaces, heat pumps, boilers, mini split systems, geothermal heat pumps, and indoor air quality products. With over 50 years of experience, Y-Tech offers professional HVAC tune-ups and maintenance agreements to help keep systems running efficiently. They also provide 24/7 emergency service to address urgent heating and cooling needs.

National Heat & Power Corp. is a heating, air conditioning, ventilation, and plumbing contractor serving the Chicago, IL area. Established in 1957, the company provides mechanical HVAC systems, process and industrial piping, steam and condensate piping, plumbing systems, temperature controls, energy management, and building automation. They offer 24-hour service and preventative maintenance contracts for commercial and industrial clients across various sectors including education, healthcare, government, and manufacturing.