CO₂ refrigerant: characteristics, advantages and applications
Frascold clears things up
A guide in the efficient and sustainable choice of CO2
In recent years, interest in natural refrigerants has grown significantly, supported by the search for increasingly advanced solutions with low environmental impact. In this sense, the adoption of natural refrigerants requires guidance to choose the most suitable technologies in a targeted way, to ensure maximum efficiency in the different application areas. Let’s discover together the features and advantages of R744 refrigerant..
The role of CO2 in terms of sustainability and technological innovation
CO₂, known in the HVAC&R world as R744, stands out as the only non-flammable and non-toxic natural refrigerant in low concentrations. Colourless and odourless, it is characterised by an ODP of 0 and a GWP of 1 as well as its excellent thermodynamic properties, such as its high volumetric cooling capacity and excellent heat exchange coefficient. Compared to other natural refrigerants, carbon dioxide stands out for its high efficiency in subcritical applications, thanks to which it is possible to create compact systems, with the same cooling capacity and by virtue of a better interaction between the temperature of the refrigerant and the secondary fluid.
CO2 between subcritical and transcritical
The distinction between subcritical and transcritical operation concerns the scope of application according to the temperature and pressure in which it operates. In detail, we operate subcritically in the presence of low temperatures and moderate operating pressures, and we operate in transcritical for medium temperature applications, in heat pumps, and in cases of thermal recovery. The low critical point of CO₂ and the high operating pressures require more robust compressors that support high stresses, able to provide the same performance as traditional systems. The challenges of the compressor are represented by higher pressures and discharge temperatures, which lead the system to work in a transcritical regime, especially where air exchangers are used on the high pressure side.
Understanding the thermodynamic characteristics of CO₂ and the challenges involved is essential to optimize the efficiency and reliability of refrigeration and heating systems that make use of this refrigerant.
Discovering the multiple applications of CO₂
The main application of R744 is commercial refrigeration even if there is a constant usage of refrigerant in heat pumps. CO₂ is establishing itself as a viable alternative to HFCs due to its characteristics that make it an efficient choice and a long-term solution, for example, for retailers that need large-scale refrigeration systems. In addition to commercial refrigeration, the R744 is also gaining traction in the heat pump industry with systems that enhance its ability to absorb and release heat effectively, for both heating and cooling. This flexibility makes the coolant particularly suitable for commercial and industrial applications, especially with high water Delta T values.
SK3 and TK HD: our solutions for CO₂
Frascold offers two CO₂ solutions: the SK3 series for CO₂ operation in subcritical applications and the all-new TK HD series for CO₂ operation in transcritical applications. The SK3 series, consisting of 15 models, operates with evaporation temperatures from -50°C to -10°C and with condensation temperatures up to 20°C, guaranteeing high energy savings and maximum sustainability in different sectors, such as the commercial, industrial and process cooling sectors, both for single-stage, booster and cascade systems.
The entire SK3 range adopts specific solutions for the reduction of delivery pulsations, which is very effective in multi-compressor installations.
The new TK HD series for transcritical CO₂ , specially designed to operate in harsh conditions, includes 4 sizes and 34 models. Thanks to the continuous innovation and field tests carried out by Frascold, the series has been optimized to work at a high delta P, high operating temperatures, and ensure continuous 24/7 operation, even under inverters, without compromising their durability over time. Their robustness and reliability make them ideal for heat pumps in industrial applications, with excellent performance and a superior life cycle. The TK HD series is distinguished by the use of highly resistant components, optimized lubrication and silent operation, with sound pressure levels at 1 meter distance, ranging from 63.8 to 76 dB(A).
Frascold offers a unique advantage thanks to the expertise of our team and our ability to turn challenges into opportunities, emphasizing quality and sustainability. Explore the SK3 and TK HD ranges to find the most suitable solution for your specific needs.
