Emerson is committed to furthering CO₂ refrigeration technologies by developing innovative solutions that make CO₂ more viable for our customers and the industry.
Environmental regulations and corporate sustainability targets have set the stage for wider adoption of CO2 in commercial refrigeration.
How are sustainability goals and emerging regulations setting the stage for widespread CO2 refrigeration adoption? Listen to Emerson’s Andre Patenaude and Sam Smith discuss in our latest podcast with ACHR.
What is the critical point of CO2? How should you store CO2 refrigerant? How do HFC refrigerant properties compare to CO2? Hear from our experts to get answers to some of the most important technical questions about unique performance and operating characteristics of CO2 refrigerants.
Emerson is continuing its commitment to CO₂ innovation by investing in the next generation of CO₂ refrigeration technologies. From compression technology to distributed architectures, we’re expanding our testing and lab capabilities to support our OEM and end user partners.
Transcritical CO₂ Booster
R-744 system that uses only CO₂ for medium temperature and low temperature refrigeration loads.
Secondary CO₂
Secondary glycol and CO₂ coolant is pumped to the refrigeration loads to provide cooling.
Hybrid HFC/CO₂
Traditional centralized DX system for medium temperature loads with R-744 subcritical cooling for the low temperature loads.
Combining compression technology, advanced facility management and CO2 system controls, VFDs, leak detection, CO2 system components and expert services, Emerson delivers seamless system integration that enables maximum system reliability, efficiency and simplicity.
Check out our full CO2 product portfolio.
Get answers to frequently asked questions
CO₂(R-744) — non-toxic, non-flammable and with a GWP of 1, CO₂ has demonstrated its effectiveness in both low-temperature (LT) and medium-temperature (MT) applications. CO₂ as a natural refrigerant poses very little threat to the environment.
The term “natural refrigerant” refers to substances that naturally occur in the environment. Unlike the synthetic refrigerants that have commonly been used in refrigeration applications — including hydrofluorocarbons (HFCs) and chlorofluorocarbons (CFCs) — ammonia (NH3 or refrigerant name R-717), propane (refrigerant name R-290) and carbon dioxide (CO₂ or refrigerant name R-744) are three naturally occurring refrigerants that pose very little threat to the environment.
CO₂ -based refrigeration systems have been successfully deployed in commercial and industrial applications in Europe for nearly two decades. Because of its low critical point and high operating pressure, CO₂ refrigeration strategies must be designed to account for its unique characteristics. In light of current environmental regulations, the popularity of these systems has increased significantly in North America in recent years.
Because CO2 refrigeration systems operate at extremely high pressures, technicians should take precautions when handling CO2. Even when the system is shut off, standstill pressures are extremely high and need to be handled carefully. In addition, CO2 can displace oxygen and release it in excessive amounts because it’s heavier than air. As a result, technicians should avoid handling it in confined spaces. But with proper training and equipment design, CO2 can be used safely.
CO₂ has unique performance and operating characteristics that differentiate it from HFCs and dictate system design. It has higher density than a typical HFC refrigerant, which translates into the use of smaller compressors. However, the motor is similar in size since the work being done is approximately the same. CO₂’s higher density means that smaller pipe diameters can be used, especially on the suction side of the system. Due to its high pressures, system components need to be rated to tolerate a higher maximum pressure rating.
When charging a CO2 refrigeration system, the most important consideration a technician should keep in mind is the triple point pressure of CO2. 60.4 psi is the pressure at which CO2 will turn to dry ice. As a result, contractors must be careful not to charge with liquid CO2 when the system is below this pressure, and instead charge with vapor until the system reaches triple point. Failure to do so will result in the formation of dry ice. There are various anecdotes about technicians — who are more familiar with charging HFC systems — charging a CO2 system with liquid and causing the formation of dry ice.
