RACA Journal I October 2026 www. refrigerationandaircon. co. za 31
FANS AND DUCTING
THE SYSTEMS BEHIND EFFECTIVE AIR MOVEMENT feature
By Eamonn Ryan
Fans and ducting are fundamental to HVAC & R systems, yet their critical role in efficient air movement and system performance can easily be overlooked once they are installed and operating.
Together, fans and ducting determine how effectively air is moved, distributed and controlled, with equipment selection, system design and operating conditions all influencing energy consumption and performance.
As efficiency requirements become increasingly important, attention is shifting from individual components to how systems perform as a whole. For fans, this includes the efficiency of motors, drives, controls and impellers, while ducting brings its own considerations around airflow, pressure losses, leakage, sizing, installation and system design.
This feature looks at both sides of the equation, from the changing requirements for fan efficiency and the impact of South Africa’ s MEPS regulations to the practical considerations that influence the performance of ducted air-distribution systems.
THE CHANGING ROLE OF THE FAN: EFFICIENCY, INTELLIGENCE AND LOCAL CAPABILITY Fans may be among the least glamorous components of an HVAC & R system, but growing pressure to reduce energy consumption, improve system control and minimise downtime is changing how they are designed and selected.
According to ebm-papst, the shift towards electronically commutated( EC) technology is making fans increasingly important to overall HVAC efficiency. EC fans combine efficient motors with integrated electronics and variable-speed control, allowing airflow to be adjusted to actual demand rather than running continuously at a fixed output. The company also sees fan retrofits as an opportunity to improve the performance of existing air-handling and ventilation systems.
The implications extend beyond energy consumption. Integrated controls can simplify installation and provide greater control over airflow, while newer fan systems can offer monitoring and connectivity that make them part of the wider building-management system.
For building owners, this shifts the calculation from purchase price towards lifecycle cost. A more expensive fan may justify itself through lower electricity consumption, reduced maintenance and improved controllability.
FROM COMPONENT TO INTELLIGENT SYSTEM The trend is particularly relevant as cooling and ventilation systems become more sophisticated. EC technology allows fan speed to be varied precisely, while digital connectivity can provide operating information to control systems.
“ Shame we couldn ' t save this... it was my biggest fan” – Nigel Pengelly, VMG Consultants.
Supplied by VMG Consultants
RACA Journal I October 2026 www. refrigerationandaircon. co. za 31