ECOFIT Backward-Curved Centrifugal Fans
RRE and RRM: Performance and Easy Integration
ECOFIT backward-curved centrifugal fans are designed for ventilation applications requiring a combination of high airflow performance, compactness, and easy integration. The range is available in two main configurations: RRE (External Rotor Backward-Curved Fan) and RRM (External Rotor Backward-Curved Fan Module).
While both are based on the same operating principle, their different designs meet specific integration requirements in ventilation equipment and systems.
How Does a Backward-Curved Centrifugal Fan Work?
In a backward-curved centrifugal fan, air is drawn axially into the center of the impeller. As the impeller rotates, the air is accelerated and discharged radially, at approximately 90° to the inlet airflow.
One of the key characteristics of a backward-curved impeller is the shape of its blades. Its design differs from that of a forward-curved centrifugal impeller and provides airflow characteristics particularly well suited to a wide range of ventilation applications. A backward-curved impeller can deliver airflow comparable to other centrifugal fans while achieving higher static pressure.
Backward-curved centrifugal fans are particularly suitable for Heating, Ventilation, and Air Conditioning (HVAC) systems, as well as a wide range of industrial equipment requiring efficient airflow.
RRE: Motor and Impeller Combined in a Compact Design
The RRE – External Rotor Backward-Curved Fan – directly combines a backward-curved centrifugal impeller with an external rotor motor.
This compact assembly forms the core of the ventilation system: the motor directly drives the impeller to generate the airflow and pressure required by the application.
Depending on the model, ECOFIT backward-curved impellers are manufactured from metal or plastic. ECOFIT also offers its E-wheel impellers, featuring a geometry specifically engineered to improve fan performance.
Impeller design plays a key role in the fan's aerodynamic performance. The blade profile and geometry are optimized to improve airflow and overall performance.
RRM: A Ready-to-Integrate Backward-Curved Fan
The RRM – External Rotor Backward-Curved Fan Module – is based on the RRE concept, with the addition of a structure specifically designed to simplify installation into the customer's equipment.
The motor and impeller are assembled within a module that also serves as a mounting support. This provides the integrator with ready-to-use mounting points for installing the fan directly into the system.
This design simplifies mechanical integration, reduces the number of additional components required around the fan, and facilitates assembly.
ECOFIT offers two types of modules depending on fan size:
- Plastic modules for impeller diameters of 175, 192, and 220 mm;
- Metal modules for diameters of 225, 250, 280, and 315 mm.
The RRM provides a ready-to-integrate solution thanks to its dedicated mounting module.
Looking for the right backward-curved centrifugal fan for your equipment? Discover the ECOFIT range and select the configuration, diameter, motor technology, and performance that best meet your application requirements.