Kaltra completes its portfolio of air-cooled units with third-generation Lightstream Screw Evo — an air-cooled chiller based on semi-hermetic screw compressors and running on green refrigerants. These chillers significantly exceed EcoDesign 2021 efficiency levels (Directive 2009/125/EC) owing to several innovations incorporated in their design.
Lightstream Screw Evo is the first range based on the new Evo platform, which involves last-generation compressors, hybrid falling film evaporators, twin-slab microchannel condenser coils with dedicated subcooler, new, state-of-the-art software — all aimed to improve energy efficiency. The capacity ranges from 300 to 1800kW, with allowable water supply temperatures of up to 24°C in standard configuration and an evaporator delta of up to 12 degrees. Acceptable ambient temperatures are up to 58°C, making Lightstream Screw Evo an all-climate solution. Three noise level reduction packages are available to order, including an ultra-low sound suppression kit for urban installations.
New units are engineered as dual refrigerant circuit systems and empowered by CSH.6 screw compressors designed for improved seasonal efficiency and feature stepless mechanical capacity regulation. Compressors feature refrigerant injection to extend the chiller’s operating envelope and refrigerant economizer. Suitable refrigerants include R513a, R1234ze(E), R450a, and R134a.
Twin-slab microchannel condensers with outer subcooler coil ensure high subcooling, contributing to further efficiency improvement. Additionally, twin-slab condenser design reduces the number of required condensers, making Lightstream Screw Evo more compact and lightweight compared to competing units of the same capacity.
Hybrid falling-film evaporator combines the advantages of a flooded heat exchanger but significantly reduces refrigerant charge (up to 50%) in comparison to the latter.
Feature-filled control software of the lineup includes tools for chiller setup, management, diagnostics and monitoring, local or remote. Evaporator flow control functionality, power analyzer, and energy metering — are now standard features. As standard, the software includes sequence management features.
New chillers have been outfitted with an all-new, lightweight frame that enables roof/gantry installation and provides easy access to unit components for routine maintenance.
Lightstream Screw Evo will be available for order starting from April 2024. Pre-orders are opening in February.
