This is Challenge Preparatory School that we've been working on for about a year now. It's a ground-up school built in the Rockaways. We gave this new build a whole new system, brand new boiler systems in the boiler room, and more!

Along with a fleet of more than 100 service vehicles and over 30 on-foot technicians, our typical response time is among the fastest in the industry, allowing us to resolve HVAC emergencies quickly and efficiently.

This rigging job has been years into planning for the Westchester Mall. The units are being rigged in overnight so that the units can be online and ready during the day.

Donnelly Mechanical’s Special Projects division is committed to delivering intelligent HVAC solutions and upgrades. Our primary focus is to provide support and resources for mechanical systems that are above and beyond the general maintenance and repair services scope.

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.