Commercial HVAC & Mechanical Contractor
Alliance is a commercial mechanical contractor serving Connecticut and New York, trusted for complete heating, cooling, and ventilation solutions.
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Advanced HVAC Solutions for Complex Facilities
Some projects require more than the basics. Alliance partners with developers, contractors, and property managers to design and deliver advanced HVAC solutions for large or specialized facilities.
New Construction HVAC
We have the experience, facilities and resources to fabricate and install ductwork, hydronic, chilled water and control systems for any new project.
Engineering & Design
Our team can provide engineering and design services for projects of any size and scope.
Tenant Fit-Outs &Â Interior Alterations
Restaurants, Data Centers, retail spaces, etc. Alliance has the experience to manage timelines by working alongside contractors and other trades.
Equipment Replacement & Upgrades
Let our retrofit experts help you select equipment and controls that will save energy and increase productivity by minimizing downtime.
Rooftop Unit Installation & Service
Rooftop units (RTUs) are a backbone of business HVAC systems. We install, replace, and service RTUs for office buildings, retail spaces, and industrial properties—keeping large-scale operations efficient and dependable.
Building Automation & Control Systems
Today’s facilities require smart controls to balance comfort with efficiency. Alliance designs and installs building automation systems that integrate heating, cooling, ventilation, and lighting into a single, easy-to-manage platform. Our controls improve energy savings while giving property managers precise oversight.
How We Help Organizations Thrive
Commercial Heating & Air Conditioning Solutions in Connecticut & New York
Your business or non-profit organization serves your most important asset: People. Providing an inviting and comfortable atmosphere to your staff, customers and visitors is our utmost concern. While the immediate benefits of happy people are apparent, the benefits of running an efficient and comfortable working environment translate into profit increases from reduced energy costs, enhanced employee productivity, and consistent quality customer experiences.
Our commercial heating and air conditioning solutions benefit corporations, developers, non-profits, and investors in Fairfield, Westport, Weston, Wilton, New Canaan, Norwalk, Darien, Stamford, Greenwich, Rye, Harrison, Pound Ridge, and surrounding areas in Fairfield, Westchester, Putnam, Duchess & Suffolk counties.
Call 203.335.9464 today to schedule service with Alliance Heating & Air Conditioning.
Trusted by businesses across Connecticut and New York for over 40 years.
Core Heating & Air Conditioning Services
The foundation of a comfortable, productive workplace is a dependable HVAC system. Alliance provides a full range of services to keep offices, retail properties, and schools running smoothly — from installation and upgrades to fast repairs and preventive maintenance.
HVAC Installation & System Upgrades
We design and install heating and cooling systems built for offices, schools, retail spaces, and industrial facilities. Whether it’s a new rooftop unit, VRF system, or geothermal solution, our installations are engineered for efficiency and tailored to the building’s needs.
By working with trusted brands like Trane, Carrier, Mitsubishi, and Climate Master, we help businesses lower operating costs while improving comfort.
Fast Repairs to Keep Operations Running
24/7 response for breakdowns, from rooftop unit failures to boiler malfunctions. When HVAC systems break down, productivity and comfort suffer. Our certified technicians provide rapid-response repairs across Connecticut and New York, handling issues from boiler malfunctions and refrigerant leaks to rooftop unit failures and control system errors.
Because our service vehicles are fully stocked, most repairs can be resolved in a single visit—minimizing downtime for your business.
Preventive System Maintenance for Business
Routine service is critical to avoid costly repairs and maintain compliance with building codes and OSHA safety standards. Alliance offers custom commercial HVAC maintenance plans designed for multi-site facilities, office buildings, retail centers, and industrial operations.
Our preventive programs cover:
- Seasonal tune-ups and filter changes
- Ductwork inspections for leaks and efficiency
- Coil cleaning to maintain airflow and performance
- Detailed reporting to help plan capital expenses
Indoor Air Quality & Ventilation
Healthy air matters in offices, retail spaces, and facilities. Alliance installs ventilation and air purification systems that reduce contaminants, control humidity, and improve overall comfort.
Key solutions include:
- Humidity control for both damp summers and dry winters
- Air purifiers and UV systems to reduce airborne particles and odors
- HEPA and high-efficiency filters for cleaner, healthier air
- Energy recovery ventilators (ERVs) to balance fresh air with efficiency
With the right IAQ upgrades, your building stays healthier, more comfortable, and compliant with ASHRAE standards.
With the right installation, routine maintenance, and fast repairs, you can extend equipment life, improve efficiency, and reduce costly downtime. Alliance has been keeping businesses comfortable since 1979 — and we’re ready to do the same for you.
Need fast repairs or reliable maintenance for your facility? Alliance offers 24/7 service and customized maintenance programs to keep your systems running smoothly.
Call (203) 335-9464 now to get started.
From rooftop unit replacements to fully automated building control systems, Alliance delivers the expertise and technology needed for complex environments. When you choose us, you’re partnering with a mechanical contractor trusted by businesses across Connecticut and New York for advanced system design and support. Call (203) 335-9464 to request a consultation with our team.
Organizations We Work With
We work with a variety of organizations throughout Connecticut and New York. Examples include retail, highrise residential buildings, corporate parks, government offices, schools, churches, temples and other religious buildings, sports facilities, and other speciality facilities.
Local Considerations for Connecticut & New York Businesses
Businesses across Connecticut, Westchester, Putnam, Dutchess, and Suffolk counties face a unique set of climate and building challenges that make professional HVAC service essential.
Seasonal Extremes: Winters bring freezing temperatures that put strain on boilers, furnaces, and rooftop units. Summers are hot and humid, which forces cooling systems to run longer hours — especially in retail stores and open-plan offices with high occupancy. Both extremes increase wear and require regular maintenance to avoid downtime.
Older Office Buildings: In cities like Bridgeport, Stamford, White Plains, and Norwalk, many office towers were built decades ago. These properties often have outdated ductwork, inefficient controls, or rooftop units nearing end-of-life. Retrofitting with modern systems improves efficiency and cuts utility costs.
Coastal Conditions: Businesses near Long Island Sound or along the Suffolk County shoreline face salty, damp air that accelerates corrosion in HVAC equipment. Protective coatings, more frequent inspections, and proper ventilation strategies are critical in these locations.
Retail & High-Traffic Spaces: Malls, grocery stores, and shopping centers generate heavy cooling loads in summer due to lighting, equipment, and foot traffic. HVAC systems in these environments must be sized and serviced to handle peak demand without failures.
Corporate Campuses & Multi-Site Facilities: Larger properties often require zoning, building automation, and precise system balancing to maintain consistent comfort across multiple floors or locations. Regular system monitoring and smart controls prevent hot/cold spots and reduce wasted energy.
Energy Codes & Compliance Requirements: In Connecticut and New York, commercial buildings must meet strict state and local energy codes. From ventilation standards set by ASHRAE to energy benchmarking in larger cities, businesses face added pressure to maintain efficient systems. Partnering with a licensed HVAC contractor ensures your building stays compliant while reducing operating costs.
By tailoring solutions to these regional and property-specific factors, Alliance Heating & Air Conditioning ensures offices, retail spaces, and facilities in Connecticut and New York stay comfortable, efficient, and compliant — no matter the season.
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