What Type of Fan Is Used in AHU? | EC & Centrifugal Fans by Belmont Fan
Publish Time: 2025-10-31 Origin: Belmont Tech
What Type of Fan Is Used in AHU?
Introduction
An Air Handling Unit (AHU) is the heart of any HVAC system — it circulates and conditions air for heating, cooling, and ventilation in buildings.
At the core of every AHU lies its fan system, which determines the airflow efficiency, pressure stability, and energy performance of the entire unit.
So, what type of fan is typically used in an AHU?
The answer depends on the design and efficiency requirements — but most modern systems now rely on centrifugal fans or EC plug fans for superior performance.
1. Centrifugal Fans in AHUs
What They Are
Centrifugal fans, also known as blower fans, use a rotating impeller to move air radially outward. They’re ideal for applications that require high static pressure and steady airflow—making them a perfect fit for AHUs.
Types of Centrifugal Fans Used in AHUs
Backward Curved Centrifugal Fans – These fans have blades curved opposite to the direction of rotation. They offer:
High efficiency
Low noise operation
Compact size
Longer lifespan
Forward Curved Centrifugal Fans – Common in smaller AHUs or units with lower static pressure requirements. They are quieter but slightly less efficient.
✅ Advantages
High static pressure handling
Energy-efficient airflow
Ideal for large commercial HVAC systems
2. Plug Fans (EC Plug Fans)
What They Are
EC plug fans are a modern evolution of centrifugal fans. They combine a backward curved impeller with an Electronically Commutated (EC) motor, delivering high performance and intelligent control.
⚙️ Key Benefits of EC Plug Fans in AHUs
Integrated speed control (no external VFD required)
High energy efficiency (up to 90%)
Low noise operation
Compact, direct-drive design — no belts or pulleys
Easy installation and maintenance
Why They’re the Preferred Choice Today
More and more AHU manufacturers are switching from traditional belt-driven fans to EC plug fans because they:
Reduce system energy consumption
Allow precise airflow control
Improve system reliability and lifespan
3. Axial Fans in AHUs
While centrifugal and EC plug fans dominate most AHU designs, axial fans are used in applications that require high airflow with low to medium pressure, such as:
Heat recovery units
Air extract or fresh air systems
Compact modular AHUs
Axial fans are known for their:
High airflow capacity
Lightweight and simple structure
Low energy consumption in low-pressure systems
4. Choosing the Right Fan for Your AHU
When selecting a fan for an Air Handling Unit, consider:
Required airflow (CFM)
Static pressure
Energy efficiency targets
Noise limitations
Space and mounting design
For modern AHU systems, EC backward curved centrifugal fans or EC plug fans deliver the best performance, combining energy efficiency, low noise, and precise control.
The most common types of fans used in AHUs are centrifugal fans and EC plug fans, with EC technology now leading the trend toward smarter and more energy-efficient air handling systems.
With 24+ years of professional experience, Belmont Fan manufactures high-performance EC centrifugal plug fans and axial fans specifically designed for AHUs, HVAC systems, and industrial ventilation.
Learn more about our EC plug fans and AHU fan solutions at www.belmont-tech.com