'%3e%3cpath%20d='M41.90,14.92%20L44.15,2.36%20L55.85,2.36%20L58.10,14.92%20A36%2036%200%200%201%2069.08,19.47%20L79.55,12.18%20L87.82,20.45%20L80.53,30.92%20A36%2036%200%200%201%2085.08,41.90%20L97.64,44.15%20L97.64,55.85%20L85.08,58.10%20A36%2036%200%200%201%2080.53,69.08%20L87.82,79.55%20L79.55,87.82%20L69.08,80.53%20A36%2036%200%200%201%2058.10,85.08%20L55.85,97.64%20L44.15,97.64%20L41.90,85.08%20A36%2036%200%200%201%2030.92,80.53%20L20.45,87.82%20L12.18,79.55%20L19.47,69.08%20A36%2036%200%200%201%2014.92,58.10%20L2.36,55.85%20L2.36,44.15%20L14.92,41.90%20A36%2036%200%200%201%2019.47,30.92%20L12.18,20.45%20L20.45,12.18%20L30.92,19.47%20A36%2036%200%200%201%2041.90,14.92%20Z'%20fill='url(%23cpGear)'%3e%3c/path%3e%3ccircle%20cx='50'%20cy='50'%20r='28'%20fill='none'%20stroke='%23012f00'%20stroke-width='3'%3e%3c/circle%3e%3cpath%20d='M43.50,37.50%20L45.50,35.50%20L54.50,35.50%20L56.50,37.50%20L56.50,43.50%20L62.50,43.50%20L64.50,45.50%20L64.50,54.50%20L62.50,56.50%20L56.50,56.50%20L56.50,62.50%20L54.50,64.50%20L45.50,64.50%20L43.50,62.50%20L43.50,56.50%20L37.50,56.50%20L35.50,54.50%20L35.50,45.50%20L37.50,43.50%20L43.50,43.50%20Z'%20fill='url(%23cpGold)'%20stroke='%23bf5d00'%20stroke-width='0.4'%20stroke-linejoin='miter'%3e%3c/path%3e%3c/g%3e%3c/svg%3e){kind=small}
Commercial HVAC Services Across Long Island
Com+ Mechanical keeps Nassau and Suffolk commercial properties running — rooftop units, chillers, boilers, VRF, and building controls for office parks, retail centers, industrial space, and medical campuses.
HVAC Challenges Common to Long Island Commercial Buildings
Aging rooftop units past their service life
Much of Long Island's office, retail, and industrial stock was built in the 1960s-80s and still runs original or first-replacement RTUs. These units lose efficiency, leak refrigerant, and fail on the hottest and coldest days — driving emergency calls and tenant complaints when capacity matters most.
Summer humidity and poor dehumidification
Coastal Long Island summers are warm and humid. Oversized or constant-volume equipment cools air without pulling enough moisture, leaving spaces clammy, fogging glass, and creating conditions for mold and IAQ complaints in offices, retail, and medical suites.
Hard winter starts and inconsistent heat
In Zone 4A, heating drives the load for much of the year. Failing gas valves, weak heat exchangers, aging boilers, and economizers stuck in the wrong position lead to cold tenant spaces, freeze risk on coils and piping, and uneven heat across multi-tenant floors.
Tenant-by-tenant hot and cold complaints
Multi-tenant office parks and strip retail commonly run many small zones off separate units or a shared system with poor controls. Without proper zoning and balancing, facilities teams get a steady stream of 'too hot / too cold' tickets that are really controls and airflow problems.
Refrigerant leaks and end-of-life refrigerants
Older systems still running on phased-down refrigerants face rising cost and limited availability for recharges. Chronic leaks become an operating-cost and compliance question, and at some point repair-vs-replace tips toward changeout.
Deferred maintenance catching up on a portfolio
When buildings are managed reactively, small issues — dirty coils, failing belts and bearings, drifting controls, clogged condensate — compound into mid-season failures. Across a multi-building portfolio, that turns into unpredictable downtime and capital surprises.
Commercial HVAC Built for Long Island's Building Stock
Long Island's commercial real estate is overwhelmingly low- and mid-rise, which means most properties here run on packaged rooftop units rather than central plant systems. Com+ Mechanical services the full spread: the office parks along the Route 110 corridor between Melville and Huntington, the warehouses and light-manufacturing buildings of the Hauppauge Industrial Park, Class A and suburban office in Uniondale, Garden City, Lake Success, and Great Neck, and the retail and big-box centers strung along Sunrise Highway, Northern Boulevard, and Jericho Turnpike. Much of this stock dates to the 1960s-80s buildout, so aging RTUs, original split systems, and oversized constant-volume equipment are common — while newer medical, life-sciences, and Class A campuses bring chiller plants, hot-water boilers, and VRF into the mix. The region sits in ASHRAE Climate Zone 4A: heating-dominant winters with humid coastal summers, which puts real demand on both heating capacity and dehumidification. Com+ provides Nassau and Suffolk property managers, building owners, and facilities teams a single-vendor portfolio relationship — service, repair, scheduled maintenance, controls, and emergency response — across one building or a portfolio spread across both counties.
Commercial HVAC Services in Long Island
Why Long Island Property Teams Work With Com+
Our Simple Process
From call to comfort in 4 easy steps
Site Assessment
We walk the building — rooftops, mechanical rooms, controls — and inventory your equipment, condition, and tenant obligations. For portfolios, we assess each property and document the full picture across Nassau and Suffolk.
Scope & Custom Quote
You get a clear, building-specific scope and a custom quote for service, a maintenance agreement, or capital work — prioritized by what's urgent versus what can be planned and budgeted.
Execution
Our technicians perform repairs, changeouts, controls work, or scheduled maintenance with attention to tenant comfort and minimal disruption, coordinating after-hours work where occupancy requires it.
Ongoing Support
With a maintenance agreement in place, we keep your systems on a proactive schedule and stay on call for emergencies — so issues get caught early and downtime stays low across your portfolio.
Types of Systems We Install
Packaged Rooftop Units (RTUs)
The dominant system across Long Island's low- and mid-rise office parks, retail centers, and industrial buildings. We service, repair, and change out single- and multi-zone packaged units, including economizer and controls work for buildings with aging or oversized equipment.
- •Service, repair, and full changeouts
- •Economizer and controls diagnostics
- •Gas-heat and electric-heat configurations
- •Curb-adapter replacements for like-for-like swaps
- •Refrigerant service and leak repair
Chiller Plants & Hot-Water Boilers
Found on Long Island's medical, life-sciences, institutional, and Class A office campuses. We maintain and repair chillers and boilers and the pumps, controls, and distribution that keep central plants running through Zone 4A winters and humid summers.
- •Air- and water-cooled chiller service
- •Hot-water and steam boiler maintenance
- •Pump, valve, and control repair
- •Seasonal startup and shutdown
- •Capacity and efficiency assessment
VRF / VRV Systems
Increasingly common in newer Long Island office fit-outs, conversions, and tenant build-outs where zoning and efficiency matter. We service and troubleshoot variable-refrigerant-flow systems and their branch controllers and controls integration.
- •Multi-zone VRF/VRV service
- •Branch controller and line-set diagnostics
- •Controls and BAS integration
- •Refrigerant leak detection and repair
- •Tenant-zone comfort balancing
Why Choose Com+ Mechanical on Long Island
Commercial-Only Focus
We work for property managers, building owners, and facilities teams — not homeowners. Our scope, scheduling, and reporting are built around commercial buildings and tenant obligations.
Full System Portfolio
From the packaged RTUs that dominate Long Island's commercial stock to chillers, boilers, VRF, and building controls, we cover the systems your properties actually run — under one vendor.
Responsive Across Nassau & Suffolk
Long Island is our service area. We coordinate response across both counties and handle multi-building portfolios spread across the Island as a single point of contact.
Proactive, Not Just Reactive
Preventive maintenance agreements are designed to catch problems before they become emergencies — extending equipment life on aging systems and smoothing out capital planning.
Transparent Pricing
No fees. No surprises. Just honest service.
Service & Repair
On-demand diagnosis and repair for rooftop units, chillers, boilers, VRF, and controls across your Long Island property.
- Troubleshooting and diagnostics
- RTU, chiller, boiler, and VRF repair
- Refrigerant service and leak repair
- Controls and BAS troubleshooting
- Repair-vs-replace recommendations
Preventive Maintenance Agreement
A scheduled maintenance program scoped to your equipment and portfolio — built to reduce emergency calls and extend system life.
- Scheduled multi-point inspections
- Seasonal heating and cooling readiness
- Filter, belt, coil, and condensate service
- Priority scheduling for agreement holders
- Single-vendor coverage across multiple buildings
- Documented condition reporting
24/7 Emergency
After-hours and emergency response across Nassau and Suffolk for when a critical system goes down.
- 24/7 emergency dispatch
- After-hours and weekend response
- Priority for maintenance-agreement holders
- Coverage across Nassau and Suffolk
Pricing is scoped after an on-site assessment of your building or portfolio. All engagements are quoted custom — no published flat rates.
Own a Commercial Property?
Business+ plans start at $499/year — includes 2 rtu tune-ups, 10% off all services, and priority scheduling.
Equipment & Brands We Service
Factory-trained technicians for all major HVAC manufacturers
%20--%3e%3csvg%20version='1.1'%20id='Layer_1'%20xmlns='http://www.w3.org/2000/svg'%20xmlns:xlink='http://www.w3.org/1999/xlink'%20x='0px'%20y='0px'%20viewBox='0%200%20150%2050'%20style='enable-background:new%200%200%20150%2050;'%20xml:space='preserve'%3e%3cg%3e%3cpath%20style='fill:%23C9202F;'%20d='M124.447,44.322c-23.807,5.229-55.19-0.102-55.19-0.102s73.175,3.979,71.344-20.254%20C138.687-1.368,35.312,8.163,35.312,8.163c60.192-10.521,91.646-0.564,93.939-0.144c11.942,3.18,19.694,9.036,20.404,15.459%20C151.563,35.271,135.269,41.943,124.447,44.322z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M83.171,38.6c-2.416,0-4.058-0.553-4.927-1.656s-1.022-2.773-0.301-5.027l4.168-12.728%20c0.861-2.684,1.97-4.478,3.324-5.382c1.353-0.904,3.469-1.357,6.35-1.357h2.956c2.877,0,4.145,0.301,5.231,1.535%20c0.934,1.06,0.972,2.521,0.108,5.205l-4.149,12.718c-0.723,2.254-1.507,4.117-3.085,5.223S88.903,38.6,86.488,38.6L83.171,38.6z%20M96.602,18.799c0.302-1.029,0.558-1.979,0.113-2.657c-0.327-0.502-0.804-0.66-1.711-0.731c-0.829-0.117-2.286-0.062-2.286-0.062%20c-1.258,0.037-2.021,0.267-2.65,0.772c-0.629,0.506-0.955,1.038-1.479,2.669L84.19,32.285c-0.406,1.26-0.455,2.143-0.151,2.65%20c0.302,0.506,1.244,0.822,2.747,0.822c1.418-0.004,2.752-0.059,3.935-0.955c0.682-0.43,1.019-1.258,1.459-2.508L96.602,18.799z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M14.834,38.18c0,0-14.646,0.014-14.643,0.002l8.314-25.357h6.201c0,0-7.508,22.517-7.448,22.517%20h8.521L14.834,38.18z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M39.008,15.701c-0.006,0,0.945-2.86,0.945-2.86H25.417c-0.002,0-0.005,0-0.005,0l-8.31,25.339H31.61%20l0.951-2.838c0,0-7.745,0-8.385,0c-0.027,0,1.516-4.672,3.201-9.758c3.337,0,7.298,0,7.294,0c-0.008,0,0.938-2.859,0.938-2.859%20s-3.821,0-7.282-0.001c0.876-2.64,1.72-5.18,2.333-7.023C34.597,15.701,39.013,15.701,39.008,15.701z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M77.25,12.821l-5.508,16.97l-2.311-16.967l-6.073,0.003l-8.253,25.356h6.074l5.537-16.979%20c0,0,2.265,16.725,2.305,16.971l-0.002,0.006l3.525,0.002l8.242-25.363L77.25,12.821L77.25,12.821z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M121.157,12.821h-4.427l-5.274,6.652l-1.309-6.652l-6.496,0.007l2.393,11.52l-10.54,13.836h4.357%20l7.112-9.356l1.94,9.352l6.226,0.002l-2.777-14.11L121.157,12.821z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M56.332,12.822l-5.511,16.971l-2.308-16.965l-6.075,0.003l-8.252,25.357h6.074l5.535-16.981%20c0,0,2.268,16.739,2.305,16.97l-0.002,0.012h3.527l8.241-25.365h-3.534L56.332,12.822z'/%3e%3cpath%20style='fill:%23C9202F;'%20d='M138.687,44.271c0,1.305-1.07,2.375-2.376,2.375c-1.305,0-2.373-1.07-2.373-2.375%20s1.068-2.373,2.373-2.373S138.687,42.967,138.687,44.271z%20M134.331,44.271c0,1.076,0.903,1.975,1.979,1.982%20c1.075-0.008,1.981-0.906,1.981-1.982c0-1.074-0.906-1.98-1.981-1.98C135.234,42.291,134.331,43.197,134.331,44.271z%20M135.688,42.98h1.022c0.559,0,0.768,0.295,0.768,0.57c0,0.533-0.334,0.695-0.616,0.834l0.42,1.08l-0.681,0.092l-0.317-1.041%20h-0.288l-0.211,1.004h-0.621L135.688,42.98z%20M136.095,44.135h0.223c0.321,0,0.524-0.189,0.524-0.48%20c0-0.156-0.124-0.295-0.327-0.295h-0.262L136.095,44.135z'/%3e%3c/g%3e%3c/svg%3e)
Don't see your brand? We service all major manufacturers! Call us to confirm.
Proudly Serving Nassau County
Fast, reliable service in your neighborhood
Frequently Asked Questions
Get answers to common questions about our services
What areas of Long Island does Com+ Mechanical cover?
We serve commercial properties across both Nassau and Suffolk counties — from the Route 110 office corridor and Hauppauge Industrial Park to retail and office in Garden City, Uniondale, Great Neck, Hauppauge, and out into central and eastern Suffolk. If you manage buildings in multiple Long Island towns, we can cover them under one relationship.
How fast can you respond to an emergency?
We provide 24/7 emergency dispatch across Long Island, and maintenance-agreement holders get priority response. Exact response windows depend on your location, the time of day, and your agreement.
Can you manage HVAC across a multi-building portfolio?
Yes. Single-vendor portfolio support is a core part of what we do. We assess each property, standardize maintenance scheduling and reporting, and give you one point of contact for every building you manage on the Island — whether that's a cluster of office-park buildings or properties spread across Nassau and Suffolk.
Does Local Law 97 apply to my Long Island building?
No — Local Law 97 is a New York City emissions mandate and applies to buildings within the five boroughs, not to Nassau or Suffolk. Long Island commercial buildings are instead governed by the New York State Energy Conservation Construction Code and state energy requirements, and many owners pursue PSEG Long Island and NYSERDA efficiency incentives. We can factor energy-efficiency and equipment-upgrade goals into your scope, but we don't position LL97 as something it isn't.
What types of systems do you service?
The full commercial range Long Island buildings run: packaged rooftop units (the most common system here), commercial chillers, hot-water and steam boilers, VRF/VRV systems, split systems, and building automation/controls. We service most major commercial manufacturers regardless of who installed the equipment.
Do I need a maintenance agreement, or can I just call when something breaks?
Both are available. You can call us for one-off service and repair, but a preventive maintenance agreement typically lowers total cost over time by catching issues early, extending equipment life on aging systems, and earning you priority scheduling — which matters most during peak summer and winter demand on Long Island.
Love Our Service? Share Your Experience!
Manage a building we've serviced? A quick review helps other NYC property managers and building owners find us.
5 stars • 500+ reviews
Most Requested Services
Our businesses' top picks for heating, cooling & air quality
Explore Commercial HVAC Resources
Equipment services, industry expertise, NYC compliance, and the metro areas we cover.
Equipment, Repair & Maintenance
Industries We Serve
NYC Compliance & Energy Law
Service Areas
Keep Your Long Island Property Running
Whether you manage a single building on the Route 110 corridor or a portfolio spread across Nassau and Suffolk, Com+ Mechanical is your single-vendor commercial HVAC partner — RTUs, chillers, boilers, VRF, and controls, with 24/7 emergency response. Request a site assessment and we'll scope a custom plan for your property.
Call (332) 600-4640