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chillers . Developments in controls ( both on-board and for plant management ) allows designers significant flexibility when considering the optimum configuration of chillers for a particular application . The data centre industry is certainly challenging chiller OEMs to find ways to reduce operating costs and many OEMs have risen to the challenge making equipment that can run with much higher-leaving chilled water temperatures ”, says Hattingh . “ We ’ re going through an exciting time at the moment . The chiller industry is in some flux as the refrigerant landscape is changing . The refrigerant changes bring about significant changes to the way in which companies then make their equipment . A refrigerant is not simply changed without significantly altering the hardware . Many OEMs are therefore experimenting with lower GWP HFCs while they work out which HFO they want to use , and they adapt their equipment to suit . Change is however something that the chiller industry is accustomed to so expect to see equipment brochures with new refrigerants and new installation procedures and requirements .”
“ There are again various technolgies that can be considered to increase efficiency . However , this must be considered in conjunction with the context of project-specific details such as cost , complexity and size requirements . For example , an air-cooled chiller can utilise dry-cooling coil sections to use low ambient conditions directly and minimise the energy required from the compressor for cooling . However , the degree to which this is effective will depend on operating chilled water temperature and the ambient conditions . It might only be a feasible option if relatively high chilled water temperatures are acceptable and if ambient conditions are suitable at a large percentage of running hours ,” adds du Plessis .
“ Some of the technology where we see development related to chiller are the EC-technology on condenser fan motors , inverter technology on compressors , connectivity of units through improved controls and the cloud based monitoring of equipment . Also worth noting is that , historically , natural refrigerants like CO₂ , ammonia and propane have been limited to big installations and specific process cooling , but natural refrigerants are now becoming more a part of the commercial side of the HVAC sector ”, notes Roelofse .
SOURCES : 1 . Daikin Airconditioning 2 . BBE Consulting 3 . Spoormaker and Partners 4 . AHI Carrier RACA
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RACA Journal I March 2021 www . hvacronline . co . za