www. refrigerationandaircon. co. za RACA Journal I November 2025 21
Events and Exhibitions airflow reliability. FanWall, making use of multiple smaller EC, offers redundancy compared to single large belt driven centrifugal fans utilised in large Air Handling Units( AHU) and built in plant rooms.
Beyond hardware, retrofits provide a chance to rethink system design: do duct runs create excessive resistance? Are filters contributing to pressure loss? Can fan placement or speed modulation improve overall system efficiency?
These are no longer theoretical questions. Tools like ISO 12759, which standardise fan efficiency measurements and calculations, help engineers and building owners quantify the real-world performance of new versus old systems – enabling smarter decisions that go beyond catalogue specifications.
While motors and systems integration are key drivers of change, advances in aerodynamics are also pushing performance boundaries. New materials and impeller shapes,
for example, reduce turbulence and improve airflow even in constrained ductwork.
One standout innovation is the rotating diffuser: a ring that spins with the axial fan impeller, reshaping how air enters and exits the fan. When utilised in axial fans, this device enables them to generate higher pressures – up to 600Pa( 4-pole) – making them viable for applications once reserved for centrifugal fans only.
These innovations challenge traditional fan design assumptions. Where engineers once defaulted to larger or more powerful fans to overcome airflow resistance, they can now achieve similar results with smarter airflow control and more efficient components.
THE SMART BUILDING ERA As South Africa and other countries enforce stricter MEPS, energy-efficient fan systems are no longer optional – they’ re a regulatory necessity. The next generation of fans won’ t just be more powerful: they’ ll be data-driven, self-adjusting and tightly integrated into smart building platforms.
Future-ready HVAC systems will use fans that:
• Adapt to environmental changes in real time
• Provide actionable performance and maintenance data
• Consume only the energy required at a given moment
• Help meet indoor air quality goals with minimal manual oversight
Supplied by ebm-papst
With EC motors, IoT integration and intelligent controls, fans are transitioning from mechanical workhorses to digital allies in the quest for cleaner, more efficient buildings.
Modern ventilation fans do more than move air – they shape comfort, energy use and indoor health. With EC motors enabling remarkable gains in efficiency and digital technologies turning fans into intelligent systems, the landscape of ventilation is undergoing a quiet but powerful revolution.
For engineers, building owners and sustainability professionals, understanding and leveraging these advances is essential. Whether through targeted retrofits or smart new installations, the opportunity is clear: better fans mean better buildings – engineering a better life. RACA
www. refrigerationandaircon. co. za RACA Journal I November 2025 21