Diagnostics & Troubleshooting
Our certified technicians perform a thorough diagnostic on your Fujitsu mini split, identifying error codes, sensor failures, and performance issues to pinpoint the root cause before any repair begins.
Queens summers are brutal and winters unforgiving — your Fujitsu mini split can't afford to fail. Denair HVAC's manufacturer-trained technicians diagnose and restore Fujitsu systems fast, often with same-day service within 4 hours. From refrigerant leaks to error codes, we keep your home or business comfortable year-round with reliable, warranty-backed repairs.
Comprehensive repair and maintenance solutions for all Fujitsu mini split and ductless systems in Queens and across NYC.
Our certified technicians perform a thorough diagnostic on your Fujitsu mini split, identifying error codes, sensor failures, and performance issues to pinpoint the root cause before any repair begins.
We detect and repair refrigerant leaks, recharge your Fujitsu system to manufacturer specifications, and restore optimal cooling and heating capacity efficiently and safely.
Fujitsu system failures don't keep business hours. Our technicians are on call around the clock, arriving fully equipped to handle urgent repairs — usually within 4 hours anywhere in Queens.
We service Fujitsu VRF and multi-zone split systems for residential and commercial properties, ensuring balanced performance across all indoor units and outdoor condensers.
Proactive maintenance plans keep your Fujitsu mini split running efficiently year-round, reducing energy costs, preventing unexpected breakdowns, and extending system lifespan.
Modernize aging Fujitsu equipment with targeted retrofits and expert tuning to boost performance, improve energy efficiency, and meet current NYC energy standards without a full system replacement.
Queens properties — from Jackson Heights apartments to Flushing commercial buildings — rely on Fujitsu mini splits for year-round comfort. Denair HVAC technicians are trained and certified by major manufacturers, meaning we understand Fujitsu systems at a level general repair services simply can't match. We arrive equipped to handle everything from nuanced error codes to compressor issues, delivering same-day service in most cases. Every repair is backed by our quality guarantee — if our work doesn't meet code requirements, we make it right.
See how Denair HVAC has restored comfort and saved money for Queens residents and businesses.
"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."
"Denair is professional and courteous."
"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."
"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."
"Denair is professional and courteous."
"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."
"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."
"Denair is professional and courteous."
"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."
"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!"
Here's what sets Denair HVAC apart as Queens' go-to Fujitsu mini split repair specialist.
Trained and certified by major manufacturers, including Fujitsu, ensuring expert-level repairs on every call across Queens.
Most Fujitsu repair calls in Queens are resolved within 4 hours — no waiting days for a technician to show up.
We refund your money if service quality doesn't meet code requirements — a promise backed by 19+ years in NYC HVAC.
Our technicians are on call around the clock for urgent Fujitsu failures across all Queens neighborhoods, any season.
Experienced professionals dedicated to keeping Queens comfortable year-round.
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.
Fujitsu mini split systems typically last 15 to 20 years with proper maintenance. In demanding environments like New York City — where systems run hard through humid summers and cold winters — regular preventive maintenance is key. Keeping filters clean, scheduling annual tune-ups, and addressing minor issues promptly can help your Fujitsu system reach or exceed its expected lifespan.
Talk to our Queens-area Fujitsu repair specialists for honest answers and a free estimate.
Denair HVAC provides Fujitsu mini split repair services across Queens and the greater New York Metropolitan Area.
11+ Regions
Service Area
24/7 Service
Emergency Availability
4.7★ Rated
Customer Rating
Contact us to confirm coverage in your area and schedule a same-day appointment.
Recognized as one of America's fastest-growing companies.
Technicians certified to the highest safety standards.
Certified by major HVAC manufacturers including Fujitsu.
Fill out the form below and a Denair HVAC specialist will get back to you promptly — most Queens repair calls are handled the same day, often within 4 hours.
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.