The 10 Year Club is a group of team members that have been with Donnelly Mechanical over 10 years. We have over 55 employees in the 10 Year Club.

I love the people most, I love the culture, I love the excitement. When we come across a challenge we are able to accomplish what we're looking to do and make the customer happy.

Since our employees play a major role in keeping our business successful, we believe in treating them the same way. The proof is in our team members – most of our licensed, certified technicians have been employed with us for over 10 years.

We are New York City’s premier provider of HVAC service, maintenance, and construction, as well as energy solutions.

As the temperatures begin to rise and summer approaches, it is important to ensure your commercial HVAC system is ready for the season. Properly caring for your system now can help you avoid costly repair bills down the line.

Basketball City is a 70,000 sq. ft. “state-of-the-art” Sports & Entertainment facility, Donnelly Mechanical helped identify ongoing issues with their HVAC equipment that included poor performance and premature equipment failure.

Have you ever been curious about how chillers work? Chillers are an integral part of many commercial businesses, providing ventilation and cooling services in a variety of sectors like construction, industrial manufacturing, and more.

Years of advocacy culminated in a bipartisan House measure being signed into law known as the American Innovation and Manufacturing (AIM) Act of 2020. This legislation will serve as an innovator to how the HVAC industry will address climate change through a responsible and gradual phasedown of hydrofluorocarbons (HFCs).