Mercedes-Benz wishes to continue using the tried-and-tested R-134a refrigerant in passenger cars

written by Pavel Makhnatch (under supervision of Rahmatollah Khodabandeh and Björn Palm)

Published Sep 28, 2012

In face of the adoption of HFO-1234yf as a low GWP refrigerant replacement to HFC-134a in mobile air conditioning (MAC) systems, Daimler AG has investigated the safeness of new refrigerant in a series of tests. The tests were held as a part of a new real-life test scenario developed in-house which goes above and beyond the legally prescribed requirements.

It was found , that “in the new real-life test scenario, the refrigerant is dynamically dispersed at high pressure near to hot components of the test vehicle's exhaust system. This corresponds to a serious head-on collision in which the refrigerant line is severed and the reproducible results demonstrate that refrigerant which is otherwise difficult to ignite under laboratory conditions can indeed prove to be flammable in a hot engine compartment. Similar tests of the current R134a refrigerant did not result in ignition.”

The company, which, among others, owns the brand Mercedes-Benz and is among the first personal car manufactures who implemented new MAC systems working on R-1234yf, is now refusing the use of this chemical in its products due to the high safety demands at Mercedes-Benz and according to the findings of the study.

Belongs to: Department of Energy Technology
Last changed: Sep 28, 2012