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Mercedes-Benz recalling SL-Class vehicles with R-1234yf refrigerant in US; replacing with R-134a

Mercedes-Benz is recalling certain model year 2013 SL-Class vehicles manufactured from 19 December 2011, through 31 May 2012 originally equipped with R-1234yf refrigerant. In September, Daimler, the parent company of Mercedes-Benz, announced that, based on internal safety testing, it would no longer use R-1234yf as a replacement refrigerant in mobile air conditioning (MAC) systems. (Earlier post.)

In the recall notice, Daimler noted that it had conducted product testing of a vehicle, not sold in the US, but equipped with the same refrigerant. According to Mercedes-Benz, the testing was designed to replicate worst-case conditions expected in a severe frontal crash that would cause a rupture of the air conditioner refrigerant line. A rupture of a refrigerant line will result in a gaseous mixture of refrigerant being released into the engine compartment.

The testing conducted by DAG determined that the escaping R-1234yf refrigerant may ignite under specific conditions. The resulting fire could spread to additional combustible materials.

Mercedes-Benz will replace the R-1234yf refrigerant with R-134a along with new refrigerant lines (hoses) designed specifically for R-134a. The remedy will be provided free of charge. The safety recall is expected to begin during October 2012.

R-1234yf has been widely accepted as a lower global warming potential replacement for R-134a in mobile air conditioning (MAC) systems.



This is a step backward to try to compensate for bad accident prone drivers.


The should simply concentrate on quality, never mind the headlines.

Multi-Modal Commuter Dude (formerly known as Bike Commuter Dude)

Any accredited engineering school will be teaching their students the four most important characteristics of a design, in a particular order:


You will not be able to control costs without staying on a schedule. You will not be able to maintain a schedule if you are forced to do rework because of low quality. Safety is primary, because if are not able to market the product due to real or perceived danger, quality is irrelevant. Finally, a couple of lawsuits brought about by "bad accident prone drivers," will adversely affect cost.

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