We Provide Solutions.

We are New York City’s premier provider of innovative commercial HVAC service, maintenance and construction. With over 30 years’ experience and 200+ employees, we serve NYC’s most prominent commercial organizations by providing innovative HVAC solutions to ensure comfort, maximum efficiency, improved indoor air quality and system reliability.

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Employee working on hvac system

Services & Solutions

We Keep Customers Comfortable with Reliable AC Repair, Maintenance, & Installation!

Preventive Maintenance

Donnelly Mechanical provides custom HVAC preventive maintenance services for a distinguished clientele within many of New York City’s prestigious buildings.

Commercial HVAC Service

Our unique NYC zoning system allows our factory trained technicians to respond quickly either by van or on foot in the event there is a service-related emergency.

Replacements & Upgrades

Our technical team goes beyond the general maintenance and repair services scope. Our turn-key client direct projects range from equipment replacements to design build solutions to high efficiency system upgrades.

New Commercial Construction

From initial survey to project completion, Donnelly effectively manages even the most complex HVAC construction projects with professionalism and ease.

Indoor Air Quality Solutions

Clean indoor air is an office amenity that matters to employees. Our experts test, monitor, improve and sustain Indoor Air Quality to ensure wellbeing and productivity for you, your employees and customers

I am writing to express my sincere appreciation for the exceptional service provided by Donnelly Mechanical We are a small independent pharmacy located in midtown, same location for 79 years. I have seen Donnelly Trucks all over NYC for decades and called to schedule an estimate My first point of contact was Thomas Rogoz. Tom's technical skills, expertise, friendly and approachable demeanor, made the experience even more enjoyable Your team's professionalism, attention to detail, and dedication have greatly contributed to the success of the project. Please extend my thanks to the entire team, Mike Morgan, Dominic C, Danny D, Stephen Croteau, Marty Cunningham, Sacha Trammell, Lysa Eldridge, Richie, and Douglas Abramowitz. Their hard work and dedication have not gone unnoticed, and I look forward to continuing our successful relationship.

Ellen Adler, President Windsor Pharmacy

I just wanted to thank you and everyone on your team for all of your help in repairing our AC issue. This was an ongoing struggle before I joined the company, with several vendors not being able to repair the unit. Your turnaround time was so fast and efficient and I can't thank you all enough for your assistance.

Tenant at 150 Broadway Senior Manager, Facilities & Environment

Donnelly’s hospitality and care that they offer their team and clients is a model I wish others would emulate. Donnelly is a great family of SMEs and Trusted Advisors who put their clients’ needs first and builds trust like only a family can. I look forward to continuing our working partnership.

Director BlackRock

A tripped circuit breaker located in the basement on the building caused our CRAC unit to go into a High-Temperature alarm and go down. Our Donnelly technician and his field supervisor responded right away. They were the absolute best. They were in constant communication with us, keeping us well informed, and were extremely professional as always. They truly represented Donnelly and what they stand for.

Director of Business Affairs Broadway Video

We retained Donnelly Mechanical to provide a turn-key replacement of obsolete air handlers. We provided the basic performance specifications we needed for the areas the equipment would serve and they did the rest from shop drawing to unit commissioning. They acted as general contractor and retained the services of all trades necessary to execute the work. Existing chilled water and steam risers required modifications as did electrical infrastructure. The project manager was present every day that work took place. He provided daily briefings on progress. Every aspect of the project was meticulously planned. The equipment being replaced was the original and thus this project presented challenges that were not a factor at the time of original installation. Everything had to fit within confines of mechanical rooms and provide adequate clearances as necessary for persons to work. I have heard tales of woe about equipment arriving at loading docks and then not fitting in the elevator, not fitting through the door, not making the turn, etc. Donnelly brought a representative from the equipment manufacturer to the site to walk the route from the street to the mechanical room so that every doorway, corridor, elevator, turn, etc was accounted for and thus there were no logistical issues that often arise in a large-scale project. All tradespersons displayed professionalism throughout and were very respectful of the property.

CHIEF ENGINEER RXR 530 5TH AVE

1,700

Distinguished Maintenance Clients throughout NYC

.58

EMR (Experience Modification Rate)

1989

Over 30 Years of Outstanding Service

200+

Employees

NYC UVGI System

Donnelly Mechanical worked to provide a safe working environment for industry employees by installing a duct-mounted UVGI system on each office floor.

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Loro Piana

With a fast-paced timeline, Donnelly replaced Loro Piana’s existing heat pump VRF system with an updated higher efficiency heat recovery VRF system.

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Long Island Healthcare Facility

With a brand new laboratory facility being constructed, new mechanical equipment was required. This included everything from new chillers, boilers, fan coil units, & custom AHUs.

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Boston Properties

The base building’s existing steam absorption chillers, which provide the large tonnage central air conditioning, had served beyond its useful life and needed to be replaced.

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Basketball City

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.

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Make the Switch

Our contract transition team makes it easy to become a preferred maintenance client.

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