BITZER HS.95 optimised for low-GWP refrigerants

Sindelfingen, 13.10.2020. The specialist for refrigeration and air conditioning technology BITZER is presenting the extension of its HS.95 screw compressors at this year's Chillventa eSpecial. In addition to significant increases in efficiency, these are now also suitable for use with low-GWP refrigerants.

The HS.95 is one of BITZER's semi-hermetic screw compressor series with four delivery volume stages in the range of 700 to 1,015 m3/h at 50 Hz, which was developed for use in large commercial and industrial applications. These compressors can be operated with low-GWP refrigerants such as R449A, R448A, R455A and R454C.

Increased efficiency

The new and bigger models of the tried-and-tested HS screw compressor series offer significant efficiency improvements of motors and mechanics, enabling a better system efficiency in full and part load operations than ever before. They are designed for a wide application range like refrigeration, air conditioning, heat pump and marine systems and can be used both in single and parallel compressor systems. In parallel operation systems with for example four compressors, system displacements of 4,060 m3/h can be reached easily.

Intelligent capacity control

The HS.95 capacity control can be performed both with the stepless mechanical capacity control CR or with external frequency inverters. The integrated double-slider technology provides the opportunity to combine Vᵢ (Internal Volume Index) and CR capacity control. The slider position detection SPI (Slider Positioning Indicator) reports the position of the two CR and Vᵢ sliders to the IQ module at all times. The IQ module constantly knows the exact operating conditions of the system due to the on-board high and low pressure sensors and automatically adjusts the Vᵢ to its optimum position. This setting causes a yearly efficiency increase of the HS.95 compressor up to 10 per cent compared to compressors without continuous Vᵢ adjustment, depending on the load profile over the year.

When operating with external frequency inverter, there is a special drive mode in which the double slider is used as a single slider purely for Vᵢ control, thus combining the advantages of speed control and automatic Vᵢ adjustment for maximum system efficiency.

Compressors with volume flows of 910 m3/h and 1,015 m3/h are already available for order, whilst preparations are under way to launch the compressors with volume flows of 700 m3/h and 805 m3/h.