Fan Arrays: Modular Fan Wall Systems for Air Handling Units
Modernize aging air handlers with modular fan array systems designed for efficiency, redundancy, and straightforward installation.
Modular Systems. Proven Performance.
A fan array is a modular system of multiple fans engineered to operate together as a single airflow solution. Designed specifically for retrofit applications, Mainstream fan arrays upgrade existing air handling units with a more serviceable, efficient, and reliable alternative to traditional single-fan systems.
Each system is custom-designed to achieve the required airflow and static pressure while fitting the space constraints of the existing unit. With custom sizing, motor flexibility, and integrated controls, Mainstream fan arrays are built to simplify retrofit projects in real-world mechanical rooms.
The Right Fan Array for Your Application
Mainstream offers multiple fan array configurations to suit different retrofit conditions, airflow requirements, and space constraints.
A heavy-duty cube-style fan array designed for larger fans, higher airflow, and higher static pressure applications. Built on a welded structural steel frame for scalable, high-performance retrofit projects.
A bulkhead-style configuration ideal for smaller air handling units. Panels bolt together in the field, with fans mounted to the bulkhead for a compact and practical retrofit solution.
Designed specifically for replacing double-width, double-inlet housed fans. Provides a familiar transition path for DWDI fan retrofits.
A high-performance option for large-volume, lower-pressure ventilation applications requiring efficient airflow and durable construction.
Where the existing casing is failing or a full fan section replacement is needed, Mainstream can provide custom air handler fan sections with fully custom dimensions.
Why Retrofit with a Fan Array?
Mainstream fan arrays replace single large fans with multiple direct-drive fans and an integrated control solution — helping building owners reduce downtime risk, lower maintenance demands, and improve controllability without replacing the entire AHU.
Built-In Redundancy
With multiple fans operating as one system, a single fan failure does not take the unit offline. N+1 redundancy can be incorporated where required, helping reduce downtime risk in critical environments.
High Energy Efficiency
Fan arrays can reduce energy consumption and operating costs by pairing efficient fan selection with precise speed control.
Zero Routine Maintenance
Direct-drive fans with sealed bearings eliminate belts, greasing, and other routine service requirements common with older fan systems.
Easier Installation
Modular construction allows components to fit through tight access points and into constrained mechanical spaces, making retrofits faster and more manageable.
Quiet, Smooth Operation
Fan arrays help reduce vibration and support quieter operation compared to older belt-driven systems.
Better Control
Integrated controls provide straightforward speed modulation, monitoring, and BAS connectivity for more precise airflow management.
30+ Years of Custom HVAC Solutions
Mainstream has been delivering custom solutions to the HVAC market for over 30 years. Strong engineering capabilities, a broad product range, and remarkable flexibility set Mainstream apart from other manufacturers in the industry.
Custom-Sized to Fit
Every fan array is designed around the constraints of your existing unit — dimensions, access, pressure, and control requirements.
American Made
All Mainstream products are manufactured at our Berkeley Heights, NJ facility. AMCA certified.
BAS Integration Ready
Panels are designed for straightforward BAS integration — BACnet MS/TP, BACnet IP, and Modbus RTU compatibility standard.
2-Year Parts & Labor Warranty
Backed by a 2-year warranty with extended coverage available.
The Right Motor for Your Application
Mainstream utilizes a range of motor types, allowing us to select the technology that best fits the project requirements, environment, and owner preference.
AC Motors
Proven and familiar for HVAC applications. Readily available, widely used, and well suited to a broad range of retrofit projects. Typically the longest expected lifespan.
PMEC Motors
Permanent magnet motors offering very high efficiency in a smaller, lighter package. Strong efficiency, long lifespan, and reliability — ideal for high-performance applications.
EC Motors
Integral electronics for simple control, high efficiency, and low cost. A strong solution for lighter-duty applications, especially where profile and access are constrained.
Specialized options: Explosion-proof, severe-duty, and stainless-steel motor configurations available for demanding or hazardous environments.
Integrated Controls for Simpler Operation
Mainstream fan arrays include control panels designed to simplify installation, startup, and ongoing operation. Panels are engineered and built to order, giving the project team flexibility to meet custom electrical and control requirements. All Mainstream control panels are UL-listed. Read more in our guide to commercial and industrial HVAC control systems.
Because controls are designed as part of the overall solution, installation and startup are more streamlined, and BAS integration is more straightforward. Factory startup and technical support is available for all Mainstream fan arrays.
Standard Features
- Single-point power with main disconnect
- Individual motor circuit protectors
- Dedicated, preprogrammed VFD per fan
- 0–10V speed signal for synchronized control
- HOA switches for local or remote operation
Premium Options
- 10" touchscreen display for live monitoring
- BAS integration — scheduling, trending, alarms
- BACnet MS/TP, BACnet IP, or Modbus RTU
- IntelliFLOW airflow monitoring
- NEMA 3R outdoor-rated enclosures
- Custom-built solutions for project requirements
Options to Match the Project
Mainstream offers a wide range of accessories and options to tailor each fan array to the application.
Fan Arrays Built in New Jersey
Looking for other industrial fan types out of the same NJ facility? See our commercial fans New Jersey page.
Want the full engineering picture across our fan and coil lines? See our custom fan solutions page.