The German manufacturing group has added five semi-hermetic models for transcritical and cascade CO2 systems to They combine robustness, high operational safety and high performance with cost efficiency.

All newly displayed compressor models feature a robust housing with high pressure strength and no bottom plate for maximum operating pressures of 42 bar and 130 bar respectively on the high pressure side. They are suitable for a wide range of applications, making them the preferred choice for a variety of system configurations and customized solutions. Their wear-resistant drive gear with further developed multilayer bearings ensures best emergency operating characteristics.
BITZER’s products are highly energy-efficient and reliable through their large-volume, suction gas-cooled motor suitable for speed regulation, as well as their efficient working valves and wear-resistant drive gear with further improved multilayer bearings. Depending on the application, they comprise two or four cylinders running quietly at low vibration levels.

BITZER’s Products

Transcritical Range: BITZER has added two models from its Octagon series for transcritical CO2 applications. The 4KTC-10K and 4HTC-20K model are well suited for an operation with frequency inverter to increase and control capacity, and for running efficiently in sub- and transcritical operation.
- Displacement (in m3/h at 50Hz): 9.6 - 12.0
- Weight (in kg): 110 - 165
- Cylinder: 4
- Oil charge (in dm3): 2.0 - 2.6
- Max. operating current (Amps at 400V-3-50Hz): 36.4/21 - 37
Subcritical Range: Ranging from 4.4 to 80 kW cooling capacity (at -35°C/-5°C), the Octagon CO2 Series are the optimal choice for subcritical CO2 low temperature cascade applications. Their design is based on BITZER’s K series which has been successfully approved in R744 projects worldwide since the 1990s. They comprise an advanced centrifugal lubrication systems by dynamic disc and integrated pulsation mufflers. Investment costs are similar to those of conventional systems. The displayed models 2EHC-3K, 4FHC-5K, and 4NHC-20K have the following basic specifications:
- Displacement (in m3/h at 50Hz): 7.81 - 46.9
- Weight (in kg): 73.5 - 153
- Cylinder: 2 - 4
- Oil charge (in dm3): 1.5 – 2.6
- Max. operating current (Amps at 400V-3-50Hz): 13.9/8.0 - 43.0


For more than 70 years BITZER has been designing and manufacturing compressors, condensing units and pressure vessels. The Germany-based group, specialized in designing screw compressors, scroll compressors, and piston compressors, has 33 subsidiaries in Europe, Asia, Australia, Africa, and America.