R.J. O’Neil Inc.

With more than 90 years of experience, this trusted contractor delivers professional HVAC-R and mechanical services across the Chicagoland area. Their reputation is built on a strong foundation of craftsmanship, innovation, and a customer-first approach, ensuring reliable comfort and safety for every project.

A key advantage for clients is access to customized maintenance packages, which help prevent costly breakdowns and extend the life of heating, cooling, and plumbing systems. These proactive plans provide stability and peace of mind for residential, commercial, and industrial properties alike.

Their wide range of HVAC-R services includes installation and servicing of chillers, boilers, rooftop units, duct systems, and mini-split solutions. Regular maintenance of these systems ensures improved energy efficiency, consistent performance, and healthier indoor air quality.

In addition, the company provides expert plumbing and pipefitting support, from installing new piping to repairing existing systems in both industrial and commercial environments. Every job is approached with precision and a commitment to long-term reliability.

Another standout feature is their 24/7 emergency service, designed to respond quickly when urgent issues arise. This around-the-clock availability allows clients to feel confident that professional help is always within reach, no matter the time or day.

As a certified woman-owned and minority-owned business, the company also emphasizes inclusivity and responsibility, making them a respected and forward-thinking choice in the mechanical services industry.

By combining technical expertise with modern solutions and decades of tradition, they continue to provide dependable heating, cooling, and plumbing services tailored to every client’s needs. Their mission is to ensure efficiency, safety, and comfort through lasting, high-quality results.