RTU Installation
What Is a Rooftop Unit (RTU)?
A rooftop unit (RTU), also called a commercial packaged unit, is an all-in-one HVAC system that sits on your building's roof and delivers heating, cooling, and ventilation through a single piece of equipment. RTUs combine a compressor, condenser coil, evaporator coil, blower fan, gas heat section or heat pump, economizer, and air filtration into one factory-assembled cabinet -- eliminating the need for a separate mechanical room inside your building.
Rooftop units are the most common commercial HVAC system in New York City, found on retail stores, restaurants, warehouses, office buildings, and strip malls. They range from 3 tons for small shops to 100+ tons for large commercial spaces, and they are built to withstand NYC's harsh rooftop conditions -- wind, rain, snow, and salt air.
How RTUs Work
An RTU draws in a mix of outdoor fresh air and recirculated indoor air. The economizer controls this mix based on outdoor temperature, allowing free cooling when conditions permit. The air passes through filters, is heated or cooled as needed, and is pushed into your building through supply ductwork. Return air is pulled back through a separate duct system, completing the cycle.
Modern RTUs use multi-stage or variable-speed compressors, modulating gas valves, and advanced controls to match output to demand -- improving efficiency and comfort compared to older single-stage units.
Ideal Applications for RTUs
Retail Stores
Single-zone or multi-zone RTUs keep sales floors comfortable without using valuable interior space for mechanical equipment.
Restaurants & Commercial Kitchens
RTUs provide make-up air and climate control to offset the massive heat generated by cooking equipment and exhaust hoods.
Warehouses & Distribution Centers
Large-tonnage RTUs handle the high-volume airflow needed for open warehouse spaces with loading dock doors.
Office Buildings
Multi-zone RTUs with VAV (variable air volume) systems provide zone-level comfort control for offices, lobbies, and common areas.
Our RTU Installation Process
Load Calculation & System Selection
We calculate your building's heating and cooling load, evaluate existing ductwork, and recommend the right RTU size and configuration for your space.
DOB Permits & Crane Planning
NYC rooftop installations require DOB mechanical permits and often crane access permits. We coordinate all permitting, crane logistics, road closures, and rigging plans.
Roof Penetration & Curb Installation
We install roof curbs with proper flashing and waterproofing to create a weathertight seal. Existing curbs are evaluated for compatibility or modified as needed.
Crane Lift & Unit Placement
The RTU is lifted to the roof by crane and set on the curb. We connect supply and return ductwork, gas piping, electrical, and controls.
Startup & Commissioning
We verify refrigerant charge, gas pressure, airflow, thermostat operation, safety controls, and economizer function before handing the system over.
RTU Repair
Rooftop units take a beating from NYC weather -- summer heat, winter ice, salt air, and constant wind exposure accelerate wear on components. When your RTU breaks down, your business feels it immediately. Fixar provides fast, reliable RTU repair across all five boroughs and Long Island.
Common RTU Repairs
Compressor Failure
Compressor burnout, locked rotor, or internal mechanical failure. We diagnose the root cause -- whether it is electrical, refrigerant-related, or mechanical -- and replace the compressor with proper acid cleanup procedures.
Economizer Malfunction
Stuck dampers, failed actuators, or bad enthalpy sensors cause your economizer to stay open in winter (freezing your building) or stay closed in mild weather (wasting energy). We repair and recalibrate for proper operation.
Belt & Blower Motor Issues
Worn belts, misaligned pulleys, and failing blower motors reduce airflow and comfort. Squealing noises, vibration, or weak airflow are common signs. We replace belts, bearings, and motors on-site.
Condenser Fan Motor
The condenser fan motor runs constantly during cooling and is exposed to rooftop weather extremes. Failed fan motors cause high-pressure shutdowns and compressor damage if not addressed quickly.
Gas Valve & Ignition
No heat calls are often caused by failed gas valves, cracked ignitors, or faulty flame sensors. We carry common ignition components and can restore heat quickly.
Control Board & Thermostat
Erratic operation, no response to thermostat calls, or random shutdowns often trace back to control board failures or wiring issues. We diagnose and replace boards for all major RTU brands.
RTU Maintenance
Regular RTU maintenance prevents breakdowns, extends equipment life, and keeps energy costs in check. Rooftop units are especially vulnerable to neglect because they are out of sight and exposed to weather year-round. Our commercial maintenance program ensures your RTU gets the attention it needs.
RTU Maintenance Checklist
- Replace or clean air filters (monthly or quarterly depending on environment)
- Inspect and clean condenser and evaporator coils
- Check and adjust belt tension and alignment
- Lubricate bearings and inspect blower motor
- Test and calibrate economizer dampers and controls
- Check refrigerant charge and inspect for leaks
- Inspect gas piping, burner assembly, and heat exchanger for cracks
- Test all safety controls (high pressure, low pressure, flame rollout)
- Clean condensate drain pan and lines
- Inspect electrical connections and tighten terminals
- Verify thermostat and control accuracy
- Inspect roof curb, flashing, and weatherproofing
We recommend seasonal maintenance -- a cooling tune-up in spring and a heating tune-up in fall -- at minimum. High-use environments like restaurants benefit from quarterly service. See our commercial maintenance plans for details.
Benefits of Rooftop Units
All-in-One Convenience
Heating, cooling, ventilation, and filtration in a single unit. No separate condenser, furnace, or air handler to install and maintain.
Saves Interior Space
The entire system sits on the roof, freeing up valuable interior square footage that would otherwise be consumed by a mechanical room.
Easy Service Access
All components are accessible from the rooftop, meaning service and repairs do not disrupt your business operations or require access through occupied spaces.
Cost-Effective
RTUs typically cost less to install than split systems or VRF for single-zone applications. Factory assembly reduces field labor and installation time.
Fresh Air & Economizer
Built-in economizers bring in free cooling from outdoor air when temperatures permit, reducing compressor run time and energy costs significantly in spring and fall.
Scalable
Available from 3 to 100+ tons. Multiple RTUs can serve different zones of a building independently, providing redundancy if one unit goes down.
RTU Brands We Service
Fixar services and installs rooftop units from all major commercial HVAC manufacturers:
Carrier
WeatherExpert, 48/50 series packaged units from 3 to 50+ tons.
Trane
Precedent, Voyager, and IntelliPak rooftop units for all commercial applications.
Lennox
Energence, Strategos, and Model L series high-efficiency commercial packaged units.
York / Johnson Controls
Predator, Sunline, and ZF/ZR series rooftop units for retail, restaurant, and office applications.
Rheem / Ruud
Commercial Renaissance line packaged units for small to mid-size commercial spaces.
Daikin / Goodman
Commercial packaged rooftop units in a wide range of capacities for budget-conscious installations.
RTU Cost Guide
Commercial rooftop unit costs depend on tonnage, efficiency rating, features (economizer, multi-stage, variable speed), and installation complexity. General ranges for NYC:
- Small RTU (3-5 tons, retail/small office): $5,000 - $12,000 installed
- Mid-size RTU (7.5-15 tons, restaurant/mid-office): $12,000 - $30,000 installed
- Large RTU (20-50+ tons, warehouse/large commercial): $30,000 - $80,000+ installed
Crane costs, curb modifications, and DOB permit fees are additional. Request a free quote for an accurate estimate based on your specific building and requirements.
Frequently Asked Questions
How long does a commercial RTU last?
A well-maintained commercial rooftop unit typically lasts 15-20 years. Units in harsh environments (restaurants, coastal locations) may have shorter lifespans. Regular maintenance is the single biggest factor in extending RTU life.
Do I need a crane to replace my rooftop unit?
In most cases, yes. RTUs are too heavy and large to carry up stairs or ladders. Crane access requires coordination with the NYC DOT for road closures and the DOB for rigging permits. Fixar handles all crane logistics and permitting as part of our installation service.
How often should I service my RTU?
At minimum, twice per year -- a cooling tune-up in spring and a heating tune-up in fall. Filters should be changed monthly or quarterly depending on your environment. Restaurants and dusty environments benefit from quarterly full-service maintenance.
What is an economizer and why does it matter?
An economizer is a damper system that brings in cool outdoor air for free cooling when outdoor temperatures are favorable -- typically in spring and fall in NYC. A properly functioning economizer can reduce cooling energy costs by 20-30%. Many economizers malfunction without anyone noticing, wasting energy for years.
Can I add zones to my existing RTU system?
Yes, with a VAV (variable air volume) system. VAV boxes installed in the ductwork allow different areas to be heated or cooled independently from a single RTU. We can retrofit existing single-zone RTU systems with VAV for better comfort and efficiency.
Should I repair or replace my old RTU?
As a general rule, if your RTU is over 15 years old and the repair cost exceeds 50% of a new unit's price, replacement is usually the better investment. Newer units are significantly more efficient and may qualify for Con Edison or NYSERDA rebates that offset the cost.
Does Fixar offer emergency RTU repair?
Yes. We provide emergency commercial HVAC service for RTU breakdowns. Call (929) 351-5179 any time for priority dispatch to your location across NYC and Long Island.
Need RTU Service?
Get a free quote for commercial rooftop unit installation, repair, or maintenance. Serving all five NYC boroughs and Long Island.
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