CHINA/GERMANY: Bitzer is debuting a new range of compact screw compressors for R134a, HFO/HFC blends and HFOs at this week’s China Refrigeration show in Shanghai.

The CSW105 series is the latest addition to Bitzer’s existing range of CSW compact screw compressors for use in liquid chillers. They were specially developed for low liquid temperatures and meet the energy-efficiency grade 1 requirements of the Chinese regulation GB19577:2015 as well as the minimum energy performance standards (MEPS) of the EU.

Bitzer is planning to launch the new compact screw compressors in four different models, with  displacements from 1,120m³/h to 2,000m³/h (at 50Hz operation).

The design of the rotor profile in the new compressor has been optimised for R134a and alternative HFO refrigerants, while the integrated IQ module CM-SW-01 enables integration into existing systems. Bitzer’s slider control is said to enable the compressors to achieve a high level of efficiency at loads of 60-100%.

Cooling capacities have also been increased. According to Bitzer, the largest model, with a displacement of 2,000 m³/h in conjunction with R134a (at an operating point of 5°C/38°C and 50 Hz operation), can achieve a cooling capacity of 1.4MW. This corresponds to double the capacity of the largest compressor model at the present time, the CSW95113. The usage limits were extended for higher evaporation temperatures, so as to enable more efficient cooling of data centres, for example.

While designed for operation with R134a, these compressors are also suitable for the HFO substitutes R1234ze(E) and R1234yf and the HFO/HFC blends R513A and R450A.

The new CSW105 screw compressors are suitable for use in water cooled liquid chillers and in air cooled liquid chillers at moderate ambient temperatures. They can be used in liquid chillers for cooling and heating as well as for low temperature heat pumps.

The CSW105 also uses Bitzer’s infinitely adjustable capacity control. The optimised slider concept for automated Vi adjustment also regulates the volume ratio independently and efficiently in a wide range of applications. The integrated IQ module CM-SW-01 with prewired sensors and actuators enables the compressors to be easily integrated into the system controls. The intelligent module then operates built-in features such as slider positioning and slider position detection or switches on oil heating if necessary. Comprehensive monitoring and recording options as well as potential remote operation via Bitzer’s BEST software is said to make operation and maintenance even simpler.

Integrated thermal monitoring for the suction gas-cooled built-in motor simplifies system integration. With their integrated oil separator, the CSW105 compact screw compressors can also be integrated into direct expansion systems, or they can be used as primary oil separators in systems with flooded and diesel evaporators. The externally accessible oil filter makes servicing easier.

Bitzer