GERMANY: Kaltra has extended its Powerstream water-cooled inverter screw chiller range with the adoption of low GWP HFO refrigerant R1234ze.

The Powerstream II chiller range was developed with a special focus on data centre and process applications. Based on a lineup of 12 models with nominal cooling duties from 400 to 1250kW, it supports supply water temperatures up to 32°C with a △t as high as 12°C. Numerous redundancy and safety options, including dual power supply, fast restart, operating map control, allow for high availability solutions for mission-critical cooling applications. 

One of the main innovations is the use of hybrid falling-film evaporators, featuring closer approach temperatures and a significant reduction in refrigerant charge.

At the same time, a built-in sequencer allows networked operation of up to eight units, featuring cooling load distribution, unit rotation, prioritisation, coordinated startup, standby control and alarm management. 

Powerstream II chillers are also fitted with a high condenser leaving water temperature kit (up to 75°C at full load), providing broad opportunities for heat recovery.

Variable primary flow feature permits a higher degree of flexibility in applications for Powerstream II chillers, while maintenance works can be carried out without interruption of operation thanks to completely independent refrigeration circuits. Each circuit runs by Bitzer frequency-controlled screw compressor, delivering efficiencies at maximum load – ESEER of 9.10 with water temperatures 25/15°C and condenser water of 30/35°C – and part-load conditions – ESEER up to 9.00 at 70% load.

Powerstream II incorporates an operator dashboard featuring real-time, data-driven performance metering, allowing customers to reduce energy consumption by up to 20%.