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Feature
information can be integrated into the control cycle , prompting the fans to adjust their speed to compensate for reduced airflow , ensuring consistent performance .
“ Initially perceived as a premium solution , the cost of EC fans has significantly decreased with the establishment of large-scale manufacturing facilities by leading brands such as ebm-papst and Ziehl . This reduction in cost has made EC fans a more economically viable choice , further accelerating their adoption across the industry .”
THE RISE OF HYBRID AHU SYSTEMS Continuing with the subject of innovations in AHUs , Mitsubishi Electric technical manager Johann Willemse and marketing director Marco Ferdinandi , discuss the evolution of AHUs , the impact of hybrid systems , and the critical role of maintenance and research and development ( R & D ).
Hybrid systems combine AHUs with variable refrigerant flow ( VRF ) systems . “ This approach involves essentially utilising a box equipped with a heat exchanger , a fan and a coil . The flexibility of VRF systems , known for their energy-saving capabilities , has made them a popular choice in the industry ,” says Willemse .
Those energy-saving attributes of VRF systems are driven by inverter compressors that make the entire system variable in capacity . This versatility allows for the development of both small-scale and large-scale systems , enabling Mitsubishi Electric to handle projects ranging from modest installations to impressive 1 000kW systems , as well as in between – as exemplified by the company ’ s recent 200kW project for a university .
The company is actively involved in projects for hospital theatre systems and other specialised spaces . “ Additionally , we frequently refurbish existing AHUs , extending their lifespan by incorporating modern advancements .”
Willemse notes that refurbishment work typically arises when AHUs are not regularly maintained , as regular upkeep maximises the lifecycle of AHUs . “ Neglecting maintenance can lead to breakdowns and excessive wear and tear – common issues faced in the South African market . In contrast , a proactive approach to maintenance would prevent potential issues .”
Another instance where refurbishment is viable , is where the internal AHU unit is still in good condition but requires technological upgrades . “ This often involves replacing outdated components , such as the heat exchanger , to comply with modern refrigerants . The refurbished unit undergoes a transformation , integrating new technology , more environmentally friendly gases , and energy-efficient features like EC fans and high efficiency filtration . This process ensures
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RACA Journal I March 2024 www . refrigerationandaircon . co . za