Brooklyn's data centers and server rooms demand precision climate control—and Liebert CRAC units are mission-critical. Denair HVAC's certified technicians deliver expert Liebert CRAC service and repair, keeping your cooling infrastructure running at peak performance. From emergency breakdowns to scheduled maintenance, we minimize downtime and protect your critical operations year-round.
Comprehensive Liebert CRAC service, repair, and maintenance solutions to keep your mission-critical cooling systems running without interruption.
Fast, reliable repair of Liebert CRAC units experiencing refrigerant issues, compressor failures, fan malfunctions, or control board errors. Certified technicians arrive fully equipped for same-day diagnostics and restoration of cooling operations.
Proactive maintenance plans tailored for Liebert CRAC systems to maximize uptime, extend equipment lifespan, and prevent unexpected breakdowns in server rooms and data centers through routine inspections and tuning.
Around-the-clock emergency response for critical Liebert CRAC failures. Technicians are on call to diagnose and restore precision cooling systems rapidly—typically within 4 hours—minimizing disruption to your critical operations.
Thorough diagnostic assessments of Liebert CRAC units to identify performance degradation, refrigerant leaks, airflow irregularities, and control system faults before they escalate into costly failures.
Modernize aging Liebert CRAC infrastructure with targeted retrofits and expert tuning. Improve energy efficiency, meet current performance standards, and extend system life without full replacement.
Smart controls and optimization strategies for Liebert CRAC systems to reduce energy consumption, lower operational costs, and maintain precise environmental conditions in mission-critical spaces.
Brooklyn's dense mix of data centers, financial offices, medical facilities, and commercial buildings relies on uninterrupted precision cooling. Denair HVAC's manufacturer-trained technicians specialize in Liebert CRAC systems—delivering meticulous service that protects servers, sensitive equipment, and critical operations. With over 19 years serving NYC's five boroughs, we understand the stakes: a failed CRAC unit can mean data loss, equipment damage, and costly downtime. Our team responds swiftly, diagnoses accurately, and restores your system with guaranteed quality.
See how Brooklyn and NYC facilities have kept their critical systems running with Denair HVAC.
"I didn't even know about their referral program sending DENAIR to one of my commercial tenants. It was a nice surprise to get paid for referral. Based on the tenant's feedback, the job was well-done. Now it's no brainer to recommend DENAIR to all my tenants"
"Great reliable HVAC company, a very rare thing to say these days — the pricing is very competitive and the work is reliable. The staff is professional and courteous, they clean up after themselves and always answer. I would recommend them!"
"Impeccable install. You can tell they're pros the moment they walk in."
"Really great to work with, awesome staff, happy to work with them anytime again in the future! Highly recommend."
"I was able to upgrade my cooling towers through the help of Denair and I did love their Service rendered, Wonderful Experience."
"What a great service. I randomly called to get multiple system inspected in my building. They came on time, done a great job and provided a detailed report. I love their transparency."
"Great company, our office was getting hotter by the minute. Denair had a tech on site with in the hour and the ac working perfect in two hours"
"Dennis was always available when I called on him. Never was any additional work generated on any quote/contract awarded. Reliable, expert and a pleasure to work with. A real value!"
"I am very pleased with the service and professionalism we receive from all the techs and staff at Denair."
"I recently used Denair for some repairs to my small two-story office building, and I have to say they are the most honest, hard-working and value focused HVAC provider I have ever experienced! Not only was the price competitive, but more importantly they helped reduce my energy costs from an..."
"They have the best Engineering Service I have ever seen; they are always available on request and perform the maintenance in the most efficient way. Great Service."
"These guys are the best. Installed my central air condition. They are quick, thorough and honest! I definitely recommend them."
"Crew was respectful, fast, and left our place spotless. Five stars."
"excellent work and quality"
"Denair is the most dependable HVAC service company in New York!"
"I didn't even know about their referral program sending DENAIR to one of my commercial tenants. It was a nice surprise to get paid for referral. Based on the tenant's feedback, the job was well-done. Now it's no brainer to recommend DENAIR to all my tenants"
"Great reliable HVAC company, a very rare thing to say these days — the pricing is very competitive and the work is reliable. The staff is professional and courteous, they clean up after themselves and always answer. I would recommend them!"
"Impeccable install. You can tell they're pros the moment they walk in."
"Really great to work with, awesome staff, happy to work with them anytime again in the future! Highly recommend."
"I was able to upgrade my cooling towers through the help of Denair and I did love their Service rendered, Wonderful Experience."
"What a great service. I randomly called to get multiple system inspected in my building. They came on time, done a great job and provided a detailed report. I love their transparency."
"Great company, our office was getting hotter by the minute. Denair had a tech on site with in the hour and the ac working perfect in two hours"
"Dennis was always available when I called on him. Never was any additional work generated on any quote/contract awarded. Reliable, expert and a pleasure to work with. A real value!"
"I am very pleased with the service and professionalism we receive from all the techs and staff at Denair."
"I recently used Denair for some repairs to my small two-story office building, and I have to say they are the most honest, hard-working and value focused HVAC provider I have ever experienced! Not only was the price competitive, but more importantly they helped reduce my energy costs from an..."
"They have the best Engineering Service I have ever seen; they are always available on request and perform the maintenance in the most efficient way. Great Service."
"These guys are the best. Installed my central air condition. They are quick, thorough and honest! I definitely recommend them."
"Crew was respectful, fast, and left our place spotless. Five stars."
"excellent work and quality"
"Denair is the most dependable HVAC service company in New York!"
"I didn't even know about their referral program sending DENAIR to one of my commercial tenants. It was a nice surprise to get paid for referral. Based on the tenant's feedback, the job was well-done. Now it's no brainer to recommend DENAIR to all my tenants"
"Great reliable HVAC company, a very rare thing to say these days — the pricing is very competitive and the work is reliable. The staff is professional and courteous, they clean up after themselves and always answer. I would recommend them!"
"Impeccable install. You can tell they're pros the moment they walk in."
"Really great to work with, awesome staff, happy to work with them anytime again in the future! Highly recommend."
"I was able to upgrade my cooling towers through the help of Denair and I did love their Service rendered, Wonderful Experience."
"What a great service. I randomly called to get multiple system inspected in my building. They came on time, done a great job and provided a detailed report. I love their transparency."
"Great company, our office was getting hotter by the minute. Denair had a tech on site with in the hour and the ac working perfect in two hours"
"Dennis was always available when I called on him. Never was any additional work generated on any quote/contract awarded. Reliable, expert and a pleasure to work with. A real value!"
"I am very pleased with the service and professionalism we receive from all the techs and staff at Denair."
"I recently used Denair for some repairs to my small two-story office building, and I have to say they are the most honest, hard-working and value focused HVAC provider I have ever experienced! Not only was the price competitive, but more importantly they helped reduce my energy costs from an..."
"They have the best Engineering Service I have ever seen; they are always available on request and perform the maintenance in the most efficient way. Great Service."
"These guys are the best. Installed my central air condition. They are quick, thorough and honest! I definitely recommend them."
"Crew was respectful, fast, and left our place spotless. Five stars."
"excellent work and quality"
"Denair is the most dependable HVAC service company in New York!"
Brooklyn facilities trust Denair HVAC for Liebert CRAC service because we combine manufacturer-level expertise with the speed and reliability that mission-critical environments demand.
Trained and certified by major HVAC manufacturers, ensuring accurate Liebert CRAC diagnostics and compliant repairs every time.
24/7 emergency availability with typical response within 4 hours—critical for Brooklyn data centers that cannot afford extended downtime.
Founded in 2007, Denair HVAC has served NYC's five boroughs and surrounding metro area for over 19 years with consistent, quality results.
We back every service with a quality guarantee—if our work doesn't meet code requirements, we refund your money. No exceptions.
Experienced professionals dedicated to keeping Brooklyn's critical systems running.
Founder & CEO
Dennis founded Denair HVAC in March 2007 with one man and a beat-up used truck right after being laid off from a 7-year career in the HVAC industry. Armed with over 17 years of hands-on HVAC expertise and deep knowledge of Brooklyn and NYC's commercial building landscape, he grew the company to $2 million in revenue within just five years. Under his strategic leadership, Denair earned recognition by Inc. 5000 as one of America's fastest-growing companies. Dennis oversees all aspects of the business—from rooftop unit replacement projects across Brooklyn's flat-roof commercial buildings to large-scale capital improvement contracts throughout the NYC metro area—ensuring every client receives honest, high-quality service.
Financial Manager
Tanya brings over 15 years of experience in finance, budgeting, and forecasting to the Denair HVAC team. She manages all aspects of accounting, financial planning, and insurance for the company—ensuring every rooftop unit replacement and installation project is backed by financial integrity and transparent cost management. Her meticulous approach to budgeting directly supports Denair's ability to offer fixed proposal pricing and value-engineered solutions that consistently save Brooklyn and NYC clients thousands of dollars. Tanya's financial stewardship has been a cornerstone of Denair's steady growth from a one-man operation to a recognized industry leader.
Lead Estimator
Farrukh has been with Denair HVAC since 2010, making him one of the company's longest-serving and most trusted team members. As Lead Estimator, he is responsible for preparing comprehensive and timely bid proposals for rooftop unit replacement and installation projects across Brooklyn and the wider NYC metro area. His expertise in tracking opportunities with vendors, subcontractors, and customers ensures every scope is accurately priced—with alternates and revisions provided for each bid. Farrukh's value engineering approach has helped Brooklyn property managers and business owners save significantly on their HVAC capital improvement budgets.
Service Manager
Thomas leads Denair HVAC's service operations, overseeing fast response times, efficient technician scheduling, and consistent service quality for rooftop unit projects throughout Brooklyn. He coordinates field technicians and customer communications to keep RTU systems running reliably—minimizing downtime for commercial tenants, property managers, and building operators. Thomas ensures that Denair's commitment to same-day service (usually within 4 hours for emergencies) is consistently met, and that every rooftop unit installation or repair is delivered with the smooth, professional experience Brooklyn clients expect from an Inc. 5000-recognized contractor.
Application Engineer
Ramil designs and supports HVAC systems tailored to the specific performance and efficiency needs of each Brooklyn building. Specializing in rooftop unit applications, he oversees equipment selection, technical planning, and engineering support to ensure every RTU installation delivers long-lasting reliability, meaningful energy savings, and full compliance with NYC building codes and LL97 sustainability mandates. Ramil's engineering expertise is particularly valuable for Brooklyn's dense stock of flat-roof commercial and mixed-use buildings, where precise load calculations and rooftop structural considerations are critical to a successful RTU replacement or new installation.
VP Business Development
Anastasiya leads Denair HVAC's business development and new client acquisition strategy, with a focus on building long-term partnerships with property management firms, general contractors, and building owners across Manhattan and the greater NYC metro area. In her role, she identifies market opportunities, develops strategic partnerships, and implements growth initiatives that have helped Denair expand its footprint across some of New York's most recognized property management companies—including AKAM, Douglas Elliman, Related, and Rose Associates. Anastasiya's client-first approach ensures that every new relationship is built on transparency, reliability, and measurable value.
Marketing Manager
Natalja oversees Denair HVAC's brand presence and client relationships, ensuring that building owners, property managers, and facility operators across Manhattan can easily discover and connect with the HVAC expertise they need. As Marketing Manager, she develops and executes strategies that communicate Denair's unique value—from 24/7 emergency availability to Inc. 5000 recognition—to the right audiences across New York City's competitive commercial real estate and residential markets. Her work building public relations and strategic outreach has played a significant role in Denair's growth and continued reputation as one of NYC's most trusted HVAC contractors.
A Liebert CRAC (Computer Room Air Conditioning) unit is a precision cooling system designed for data centers, server rooms, and other mission-critical environments. Unlike standard commercial HVAC equipment, CRAC units maintain extremely tight temperature and humidity tolerances. Specialized service is required because improper handling can compromise cooling precision, void warranties, and risk data loss or equipment damage.
Speak directly with a certified CRAC technician for fast, expert answers.
Denair HVAC provides Liebert CRAC service and repair across Brooklyn and the entire NYC metro region.
11 Regions
Service Area
24/7
Emergency Availability
Within 4 Hours
Response Time
Contact us to confirm coverage and schedule your Liebert CRAC service today.
Named one of America's fastest-growing companies.
Full OSHA safety compliance on every job site.
Factory-trained on all major HVAC and CRAC brands.
Fill out the form below and a certified Denair HVAC technician will follow up promptly to schedule your service, provide a free estimate, or respond to your emergency CRAC repair request.
For immediate assistance, feel free to give us a direct call at 718-791-5074.
For immediate assistance, feel free to give us a direct call at 718-791-5074.