Brothers Cold: The refrigerants of the future WT69 / R469A and WT77.

The future-proof substitutes for R23 for new and old chambers.

The EU F-Gas Regulation makes innovation for environmental simulation more in demand than ever. We recognized the signs of the times at an early stage and cooperated with key partners in search for R23 replacements. The results of our research are WT69 / R469A and WT77, the refrigerants of the future.

Without compromise to –70 °C.

With WT69 and WT77, the test results remain reproducible.

Our first premise and the biggest challenge in the development of the new refrigerants was to sustain test results comparability. The reproducibility of the test results is our big promise.

That's why we do not compromise on reaching -70 ° C with the new refrigerants. With WT69 and WT77, our test cabinets behave almost identically to the predecessor models with R23. The cooling rate stays linear for a long time, with high heat compensation. Therefore you can continue to use all test profiles without restrictions, and the results remain comparable.

GWP reduction of more than 90%.

With GWPs of just 1,357 and 1,516 both WT69 and WT77 comply with the EU F-Gas Regulation.

WT69 and WT77 have an extremely low GWP of only 1,357 and 1,516. Compared to R23 we achieve a CO2 equivalent reduction of over 90% (14,800). By using WT69 or WT77, you can continue to operate your systems safely beyond the year 2030 and avoid future price increases and availability problems related to R23.

Award-winning refrigerant

WT69 / R469A wins innovation award

The jury of the German Innovation Award (GIA) has honoured WT69 / R469A twice: In the category chemical industry with the prize in gold on the 1st place and in the category energy solutions as "winner". Since 1954, the German Design Council has been awarding the prize to innovations that have a lasting effect.

And at the German Innovation Award (DIP) of WirtschaftsWoche, Accenture and EnBW, WT69 / R469A was among the best 3 in the category medium-sized businesses.

Absolutely safe.

WT69 and WT77 fulfill all requirements for refrigerants in environmental simulation systems.

In the environmental simulation chambers, products are tested under extreme conditions. The extreme temperatures prevailing in the test room also present special challenges to the refrigerants in use. For example, they must not be flammable or toxic.

The new refrigerants WT69 and WT77 meet all refrigerant requirements for environmental simulation. They are:

  • Non-flammable: A1/A1 proven by ASHRAE
  • Non-toxic: material safety data sheet officially released
  • Without ODP: formula without ozone-depleting substances
  • Non-corrosive: 100,000 hours tests without corrosion
  • Chemically stable: ASHRAE and BAM tests passed

In addition, the pressure in the system remains manageable, the pressure levels do not change.


Test chambers of almost all product families available with WT69, retro-fit kits available for WT77.

The best refrigerant does not make sense if it does not work in practice. Having that in mind, we also tested the suitability of WT69 and WT77 in our test chambers. In 200,000 hours of testing over the past six years, we have tested more than 50 system configurations – all with the same result: The test chambers run flawlessly with WT69 and WT77. 

Retrofits with WT77 is possible for older test chambers of all generations.

Details about the current procurement-situation of refrigerants

Here you can download details about the current procurement-situation of refrigerants, about the F-gas regulation and its implications on the owners of climatic chambers.