USA: Johnson Controls has added the Quantech QWC4 water-cooled screw chiller to the brand’s expanded chiller portfolio for the North American market.
The use of a variable speed drive saves energy during 99% of operating hours spent at off-design conditions, with the technology reducing energy costs and carbon emissions by as much as 30% compared to traditional chillers.
The QWC4 is available in sizes from 120 tons to 300 tons, with one or two compressors.
Johnson Controls maintains that since the Quantech QWC4 screw chiller is capable of handling a higher-pressure lift than a centrifugal chiller, it can be used in both thermal storage and heat pump applications. The variable speed drive technology provides the chiller flexibility in handling high-lift applications with the highest efficiencies available. This allows the chiller to use a wide range of heat-rejection methods, including an open cooling tower, dry cooler, adiabatic cooler, heat recovery or heat pump.
The QWC4 is designed for R134a refrigerant but is said to reduce its environmental impact by directly managing refrigerant charges and potential leak points. The incorporation of a falling-film evaporator enables the refrigerant charge to be lowered by as much as 30% compared to standard chillers.