CO2 As A Refrigerant – IIAR Standard

(source article:  “IIAR Moves Forward on CO2 Standard”, November 2019 Condenser Magazine)


Is CO2 as a refrigerant an option for you?  Carlson & Stewart Refrigeration, Inc. can help point you in the right direction.  CO2 is certainly gaining in popularity in the United States and more and more experience and guidance are supporting this popularity.

IIAR (International Institute of Refrigeration) has been a long-time advocate of ammonia as a refrigerant because it is naturally occurring.  CO2 is also naturally occurring and so IIAR has embraced CO2 as they are ideally suited to helping support its use.

A recent article in the IIAR “Condenser” magazine, titled “IIAR Moves Forward on CO2 Standard” helps explain why and how a CO2 standard will benefit the refrigeration industry.  In the article, John Collins, industrial sales manager for Zero Zone and chairman of the IIAR committee developing the standard, says “It will be a document that end users, contractors and business operators can reference and know it is covering what they need for CO2.”

CO2 is a compound that can be used as a refrigerant, like any other refrigerant, because it has a boiling point suited to the realm of refrigeration.  The pressure/temperature relationship of CO2 generally leads to higher operating pressures.  These higher pressures have led to the 2 main challenges for CO2.

First is materials and equipment rated for the higher pressures.  Compressors, valves, heat exchangers, etc. have been needed to be designed and rated to accommodate the system needs of CO2.  As more and more equipment manufacturers develop CO2 compatible equipment, these higher pressures are becoming less and less of challenge.

The other challenge for CO2 has been experience.  There simply haven’t been all that many CO2 systems designed and installed in the united states.  So, there hasn’t been a large need for engineering/design guidance.  This is where the new IIAR standard will step in.

IIAR’s organizational expertise on refrigeration engineering as well as their expertise in developing trustworthy standards make it ideally suited to providing the guidance that the industry needs to safely, efficiently and effectively implement CO2 refrigeration systems.

So, if you have been thinking about a new refrigeration challenge and are trying to figure out which of the many different types of refrigeration systems will work best for you, know that CO2 is certainly a real option.   Carlson & Stewart Refrigeration, Inc. is ready and willing to provide any guidance you may need.  Give us a call and we’ll “Take the Heat for You.”

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