
While some carmakers have signified their intent to use the R1234yf refrigerant for their products' air-conditioning system as early as next year--citing its lower global warming potential over the widely used R134a refrigerant--Daimler, the maker of Mercedes-Benz, has revealed that it will continue using the latter for its products.
According to Daimler, it has carried out a series of tests on the new refrigerant "as part of a new real-life test scenario developed in-house, which goes above and beyond the legally prescribed requirements."
In these real-life test scenarios, the refrigerant was dynamically dispersed at high pressure near the hot components of the test vehicle's exhaust system to simulate a serious head-on collision where the refrigerant line is severed. Based on the reproducible test results, Daimler proved that the R1234yf refrigerant, while difficult to ignite under laboratory conditions, can indeed be flammable in a hot engine compartment. Similar tests of the current R134a refrigerant did not result in ignition.
"Due to the new findings of this study and the high safety demands at Mercedes-Benz, this chemical (R1234yf) will not be used in its products," Daimler said in a statement. "The company therefore wishes to continue using the proven and safe R134a refrigerant in its vehicles. Daimler has already informed the relevant authorities of these facts and will also make the results of this investigation available to all relevant associations as well as to other vehicle manufacturers."