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heat pump VRF . In general , rotary compressors offer a better part load efficiency than scroll compressors and scroll compressors have a better full load efficiency . The scroll compressor has seen improvements in the last decade . The inverter technology allows compressor frequency changes of 0.1Hz to 1Hz , depending on
AHI Carriers the manufacturer , and this contributes to precise capacity control resulting in end-user comfort and increased energy efficiency . Minimum compressor frequency of 15Hz to a maximum frequency of 115Hz but this is manufacturing depended .
“ Outdoor units with multiple compressors and inverter circuits can operate with only one compressor at minimum frequency which increases efficiency even further and allows for backup operation during a compressor mechanical failure or inverter PCB failure ,” he suggests .
Numerous Teraco projects ranging from pre-treating fresh air to humidity control hybrid units . These projects utilised Light Commercial outdoor units and VRF outdoor units connected to custom built AHUs .
“ There is a saving on operating cost , improved energy efficiency and ‘ green ’ certificate rating . Where there are multiple tenants they can each be individually billed and it permits remote operation and monitoring .”
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RACA Journal I June 2023 www . refrigerationandaircon . co . za