CO2 retail display cabinet testing

CO2 retail display cabinet testing

The use of CO2 (R744) as a refrigerant has been increasing rapidly. This is mainly due to CO2 being a non-flammable, natural refrigerant with a global warming potential (GWP) of 1. This makes it particularly suitable for industry sectors where users are unable, or do not wish, to use other natural refrigerants such as hydrocarbons or ammonia.

In 2020 Shecco estimated that there were 35,500 transcritical CO2 installations globally. Europe is leading the world in the roll out of CO2 with 29,000 installations. Since 2018 the number of CO2 installations in Europe has increased by 81%. In Europe 95% of the installations have been in retail stores (90% in supermarkets and 5% in convenience stores).

Due to the rapid take up of CO2 in supermarkets there is greater interest in testing retail display cabinets with CO2 as the refrigerant. RD&T therefore started developing a system to be able to meet this demand early last year.

The EN23953 test standard is used in Europe for assessing the energy and temperature performance of display cabinets and for mandatory energy labelling of cabinets. Testing remotely operated cabinets to this standard requires specialised refrigeration plant that is very different from a typical supermarket plant. When testing, the refrigeration system needs to be able to be accurately controlled to ensure consistent supply of sub-cooled liquid to the cabinet with well controlled evaporating temperature. The plant has to operate when the cabinet is on defrost and be capable of supplying liquid at the correct conditions to the cabinet immediately after the defrost terminates. This is relatively simple with an HFC plant but is far more complex when dealing with the high pressures and greater complexity of a CO2 system. To enable a testing system to be developed, RD&T worked with Star Refrigeration who designed and built a CO2 system for retail display cabinets. The system has now been in operation for over 6 months and has been shown to be very reliable and well controlled. RD&T now have staff who are trained to use the system and so we are able to install cabinets rapidly whenever required. We are delighted to be able to offer CO2 as a new testing service in addition to being able to test using other low GWP refrigerants and obviously refrigerants such as hydrocarbons in smaller integral systems.

If you would like further information on testing retail display cabinets using CO2 as the refrigerant, please contact Judith Evans at RD&T (

We would like to thank WECA and ERDF for their contribution to support the installation of the new CO2 plant through a Green Business Grant.

We will not pass this on or use for other purposes unless you provide us with specific permission to do so.