BRUSSELS: Infringement proceedings against Germany over its failure to abide by the MAC directive could be initiated as early as this week.

Reports from Germany suggest that Daimler’s failure to end its use of R134a in its car air conditioning systems in new marques of cars could bring legal proceedings this week with Germany appearing in the European courts next month.

After a number of deadline extensions, directive 2006/40/EC on mobile air conditioning – commonly known as the MAC Directive – became fully applicable on January 1 last year. Under the directive all new car models are forbidden from using a refrigerant with a GWP in excess of 150, effectively banning R134a with its GWP of 1300.

In 2012 Daimler carried out tests on the car industry’s preferred replacement, R1234yf, which they say showed that in the event of a collision the refrigerant was not safe due to its flammability. It also cited the resulting release of toxic hydrogen fluoride gas as a further danger to occupants and emergency services.

While subsequent tests by the SAE and other car manufacturers declared R1234yf as safe, the German car manufacturer continued to use R134a while pursuing the alternative development of CO2.

Ironically, CO2 was first developed for car air conditioning systems as long as 12 years ago and was initially the preferred option for the replacement of R134a. There were, however, perceived drawbacks in the use of CO2, particularly in terms of system costs and question marks over its efficiency.

The development of the low GWP HFO R1234yf around 2008 appeared to answer the manufacturers’ concerns and despite its high cost and “mild flammability” was adopted by most manufacturers as the preferred option as it enabled them to use existing technology.

While German car manufacturers appeared to initially maintain their preference for CO2, they eventually fell into line with the rest of the world, the manufacturers’ association, the VDA, expressing its desire for a global standard. At the time, VDA president Matthias Wissmann said that it was very unlikely that investigation of natural and chemical refrigerants could be done in parallel, and impossible for the Germans or Europeans to develop a solution of their own, in view of the state of the global market. He called for a worldwide standard and maintained that separate individual solutions were not an option, particularly amongst German car manufacturers.

Even so, the amount of development and testing required for R1234yf meant that manufacturers were unlikely to meet the original MAC directive deadline of January 1, 2011. After granting a number of extensions, the European Commission has not been impressed with Daimler’s refusal to comply with the MAC directive, particularly as no other tests have so far backed Daimler’s safety concerns over 1234yf.

In addition to CO2, other options to 1234yf, like Mexichem’s AC6 are are also being tested but it is not known when they might be commercially available.