The increasing demand for energy efficiency in HVAC installations means that manufacturers of ventilation equipment are increasingly seeking solutions that combine high efficiency with consistent performance under real operating conditions. A response to these needs is the Z-Shape series of centrifugal fans, which integrates advanced impeller aerodynamics with energy-efficient EC motor technology.
The new design has been developed for operation in air handling units (AHU), rooftop units and industrial ventilation systems with increased flow resistance. Thanks to the optimised impeller geometry, high static efficiency and stable operating characteristics were achieved across a wide range of operating points.
Z-Shape aerodynamics – optimising airflow
A key element of the design is the innovative Z-shaped impeller geometry. The carefully engineered blade profile improves the guidance of the air stream within the impeller, reducing flow separation and turbulence.
The main benefits of this geometry include:
- optimized airflow path
- reduced aerodynamic losses
- stable fan operating characteristics
- improved pressure build-up across the full operating range
As a result, static efficiency of up to 73% can be achieved at the Best Efficiency Point (BEP).
In practical terms, this translates into higher ventilation system energy efficiency and lower electricity consumption while maintaining high airflow performance.
Performance engineered for genuine HVAC installations
When designing the Z-Shape series, the focus was not only on laboratory performance but mainly on real operating conditions in HVAC systems.
Fans in this series offer:
- airflow performance of up to approximately 25,000 m³/h
- maximum static pressure of up to 1600 Pa
- stable operation across a wide performance range
- reduced pressure losses thanks to optimised construction.
In practice, this means they can be used both in new ventilation installations and retrofit projects, where compatibility with existing infrastructure is essential.
Performance characteristics – curve analysis
The aerodynamic features of the Z-Shape series include both airflow and efficiency curves.
Airflow characteristics
Airflow curves show the relationship between:
- airflow rate (m³/h)
- static pressure (Pa)
As airflow increases, a typical drop in pressure is observed, characteristic of centrifugal fans. Maximum pressure values occur at low airflow rates, while the highest efficiency is achieved near the Best Efficiency Point (BEP).
The operating range of individual models covers flows from several thousand to over 20,000 m³/h, enabling use in a wide range of air handling units.
Airflow curve 10VDC
Efficiency characteristics
The efficiency curves show that the highest efficiency occurs in the mid-range of the fan’s operating spectrum. This is where HVAC systems most frequently operate, which is why the design has been tailored for typical working conditions.
Efficiency 10 VDC
Energy-efficient EC technology
Z-Shape fans are equipped with high-efficiency EC motors that provide:
- high energy efficiency
- smooth speed control
- low power consumption
- long service life.
Additional solutions improve electromagnetic compatibility and operational safety, including:
- integrated EMC filter
- protection against overheating and overload
- minimized EDM (Electrical Discharge Machining) phenomenon
- low harmonic distortion of current.
Integration with building automation systems
EC motors allow precise regulation of fan operation and integration with building management systems (BMS).
Available control methods include:
- 0–10 V DC
- PWM
- Modbus
This enables the system to accurately adjust airflow parameters to current demand, thereby enhancing the energy efficiency of the installation.
Design optimised for air handling units
The Z-Shape series was developed with HVAC equipment integration in mind.
Key design features include:
- compact construction suitable for installation in air handling units
- available impeller diameters of 450 – 630 mm
- motor protection class IP54
- aerodynamic inlet cone
- compact mounting plate.
Thanks to the compact design, the fans can be easily used in both new devices and modernised installations.
Applications of Z-Shape fans
Fans from the Z-Shape series are suitable for many types of ventilation systems, including:
- air handling units (AHU)
- rooftop units
- industrial ventilation systems
- systems with high airflow resistance
- retrofit projects in existing HVAC installations.
Thanks to the wide performance range and high energy efficiency, they can be used in both commercial buildings and industrial applications.
Ready for ErP 2026 requirements
Increasing regulatory requirements for the energy efficiency of ventilation equipment mean that manufacturers must design solutions that comply with future standards.
The Z-Shape series has been designed to comply with the ErP 2026 directive, without enlarging the equipment or compromising performance parameters.
Summary
Z-Shape centrifugal fans represent a modern approach to HVAC component design. By combining advanced impeller aerodynamics with high-efficiency EC motor technology, the series delivers high efficiency, stable operating characteristics and easy integration with building automation systems.
As a result, the Z-Shape series offers an effective solution for both air handling unit manufacturers and HVAC designers seeking high-efficiency, reliable ventilation components.
Author: Marek Skarżyński, Technical Support Manager, AFL MOTORS
Leaflet Z-Shape fans
Check out the technical leaflet
