STULZ CyberAir 3PRO DX is a proven precision cooling solution that has already demonstrated its reliability and energy efficiency on the Estonian market. STULZ is now continuing the development of its successful GE series with the new CyberAir 3PRO DX GE4/GE4S generation, featuring low-GWP R454C refrigerant. Rather than being an entirely new product, it is an evolution of proven technology, developed to meet both current and future requirements for data centre cooling.
The units offer cooling capacities from 24 to 71 kW, covering a wide range of capacity requirements. A broad selection of configurations and optional equipment allows the units to be tailored to the specific needs of each project.
Dynamic free cooling for improved energy efficiency
The CyberAir 3PRO GE series offers dynamic free cooling, making use of lower outdoor temperatures whenever conditions allow. This reduces the need for compressor-based cooling and, in turn, helps lower overall system energy consumption.
The STULZ control system automatically selects the most suitable operating mode based on both the outdoor temperature and the actual cooling load. When required, free cooling and compressor cooling are combined to deliver the necessary cooling capacity as efficiently as possible.
GE4 or GE4S – compressor technology to suit the application
CyberAir 3PRO offers different compressor options to suit the load profile and energy-efficiency requirements of each installation:
- GE4 uses an on/off compressor and combines compressor cooling with indirect free cooling.
- GE4S features a variable-speed EC compressor, enabling the cooling capacity to be matched more precisely to the actual load and improving efficiency, particularly under partial-load conditions.
Both versions retain the free-cooling benefits characteristic of the GE series, while the variable-speed version provides even greater flexibility in capacity control. In STULZ system terminology, these configurations follow the GE and GES operating principles.
R454C refrigerant reduces environmental impact
The new-generation units use R454C refrigerant, classified as A2L and featuring a Global Warming Potential (GWP) of 148. This is significantly lower than that of many HFC refrigerants that have been widely used to date.
The use of R454C helps reduce the potential climate impact of the cooling system and supports the transition towards solutions that comply with the requirements of the EU F-gas Regulation 2024/573. Low-GWP refrigerants are becoming increasingly important in the cooling of data centres and other mission-critical technical environments, both in new projects and when upgrading existing systems.
Integrated safety concept for reliable operation
The use of R454C involves specific safety requirements, which have been taken into account in the design of the unit. The refrigerant circuit of the CyberAir 3PRO GE4/GE4S is certified and tested for permanent leak tightness, while the internal design of the unit is optimised to prevent refrigerant from accumulating.
Two explosion-proof gas sensors located in the unit housing and control cabinet continuously monitor refrigerant concentration. If a potential leak is detected, the system automatically activates the prescribed safety measures and triggers an alarm. This integrated approach enables the benefits of R454C to be used safely even in data centres and server rooms with demanding reliability requirements.
Intelligent control and straightforward integration
STULZ also places strong emphasis on ease of operation. CyberAir 3PRO DX GE4/GE4S units are equipped with the E² touchscreen control system, providing convenient monitoring and management of the cooling system.
Supported communication protocols include Modbus RTU, BACnet IP, BACnet MS/TP, HTTP and SNMP, allowing the precision cooling units to be integrated into existing building automation or BMS systems. Control functions also include event and trend logging, unit identification, access control and emergency operating modes.
CyberAir 3PRO DX GE4/GE4S combines STULZ precision cooling technology proven on the Estonian market, dynamic free cooling and low-GWP R454C refrigerant. The result is a solution that retains the established strengths of CyberAir 3PRO while being better aligned with increasingly stringent energy-efficiency and refrigerant requirements.
Sustainability and energy efficiency at the core
CyberAir 3PRO DX GE4/GE4S reflects STULZ’s continued commitment to providing precision cooling solutions that combine advanced technology with modern design, ease of use, energy efficiency, scalability and reliability. The use of R454C throughout the CyberAir 3PRO DX GE4/GE4S range helps reduce refrigerant-related greenhouse gas emissions and further strengthens the system’s sustainability credentials.
