Powerstream Screw

INFINITE CAPACITY CONTROL • HIGH SEASONAL EFFICIENCY • PROVEN RELIABILITY

Chiller design incorporates compact screw compressors with mechanical capacity control: the cooling capacity controlled by a slider, which allows an adaptation of the compressor displacement to the power requirement by shifting the start of the compression process through the axial movements of the control slider. The slider, starting from the full load position (100%), can be infinitely adjusted to a nominal of 25%. Resultant seasonally weighted energy efficiency is high, exceeding industry standards for screw compressors.

The perfect match of refrigerants and compressor guarantees stable operation under extended operating limits with higher pressure ratios and lower condensing temperatures compared to earlier compressor generation. Robust, low-vibration design of the compressors contributes to long chiller service life and minimum maintenance costs.

FULL CONTROL FOR CHILLED WATER PLANTS

The chiller control system is an intelligent control solution designed to meet customer demands for the efficient operation of cooling systems and giving complete control for plant operators. The control software can manage stand-alone chiller or multiple units via a sequence controller enabling unit configuration to suit ongoing cooling demand and user-specific requirements:

• Dynamic cooling demand adjustments
• Compressor rotation
• Constant superheat control
• Head pressure control
• Connectivity/networking options
• Intelligent auxiliary controls
• Smart alarm handling

The chiller provides direct linking to the building management system (BMS) for collecting operating data for event response activity and further analysis.

Using control software, the units can be configured for constant or variable flow control depending on cooling plant configuration (primary-only or primary/secondary systems) and customer requirements. Flow control logic dynamically adjusts the pump speed based on actual load, optimizing energy consumption for the chilled water plant.

ADOPTED FOR PART LOAD CONDITIONS • ENABLES HIGH EVAPORATION TEMPERATURES

​Flooded shell-and-tube evaporator used in Powerstream design offers extremely high evaporating temperatures for a given supply water temperature and optimized for refrigerant R134a and HFC/HFO blends. The heat transfer rate of the evaporator enhanced with internal refrigerant side tube grooving and optimally positioned baffles. Internal baffles in the water circuit optimize the flow while keeping pressure drop to a minimum. Reduced baffle spacing ensures high heat transfer at low flow rates, as well as for brine operation.

EASY OF MAINTENANCE/CLEANING • OPTIMIZED FOR HFC/HFO

Powerstream chillers feature newly developed shell-and-tube water-cooled condensers optimized for refrigerant R134a and HFC/HFO blends to provide the best possible efficiency. With high-grade finned tubes, the new design of the internal baffles and shell, these condensers provide lower condensing temperatures and maximum efficiency with a low cost per kW, as well as the shorter length and reduced weight.

Optimized water flow also reduces the risks of fouling and erosion of the heat exchanger, while reduced pressure drop enables savings on pump energy. New heat exchangers allow the extended range of condensation temperatures, making the chiller suitable for almost any kind of application.