R-469A

This blend was developed by TU Dresden and Weiss Technik (a member of the Schunk Group of companies).^[1] The impetus for the development thereof was the restriction in use of the refrigerant Fluoroform (R-23) by EU regulation 517/2014 ^[2] on fluorinated greenhouse gases. At that time, R-23 was the refrigerant used most often to achieve temperatures as low as –70 °C. Since 2014, R-23 has only been allowed to be used in new refrigerating equipment and devices within the context of transitional regulations. This has led to a significant shortage of the quantity available and an enormous increase in price.^[3]

The aim of the project was to develop a new refrigerant suitable for temperatures down to –70 °C that fulfilled the requirements of the EU regulation and was neither flammable nor toxic. In 2019, the blend was registered with ASHRAE for the assignment of an R-number, which was allocated in the same year.^[4]

R-469A is a chemically stable, transparent and odourless gas mixture.^[6] Since it is non-toxic and non-combustible, it has been placed in safety group A1. The global warming potential (GWP) ) of R-469A is 1357 and thus less than 10% of the value for R-23 (GWP 14800^[2]). Thanks to the low GWP value, it fulfils the requirements of EU regulation 517/2014 on refrigerants for new systems even without the certificate of exemption otherwise necessary. Systems using the refrigerant R-469A up to 3.6 kg filling quantity are exempt from the Leak test in accordance with EU regulation 517/2014.^[7]

R-469A is used in climate simulation test chambers for reaching temperatures as low as –70 °C. It is used as a substitute for R-23. The properties of R-469A with regards to cooling rate, thermal compensation, and air distribution are almost identical to those of R-23. This makes the test results of systems using the two refrigerants directly comparable.^[8]

• WT69