Why a good cabin air filter is so important
Good cabin air filters are technical masterpieces. They prevent dust, pollen, and even odours from getting inside the vehicle. Given that air is actively blown into the passenger compartment, without an air filter the concentration of pollutants in the interior of a car would be six times higher than at the roadside! It’s therefore crucial that the filter functions reliably.
Quality makes all the difference!
High-quality cabin air filters generally have a service life of at least one year or 20,000 kilometres, and a separation level of > 99.5% (almost 100%). They must be able to hold a lot of dust over a long period of time. Some filters have a filter surface of 0.25 sqm, whereas others have up to 0.6 sqm—it is easy to imagine how big the differences in performance are.
Needless to say, installation space is generally limited—it depends on the material and the geometry of the filter. Fleece filters, for example, can be pleated in such a way that a large surface area can be housed in the smallest space. However, the individual pleats require enough space for the dirty air to penetrate right to the depth of the pleats. The distance between the peaks of each pleat is normally 5 mm.
In addition, manufacturers of high-quality cabin air filters, such as MAHLE no longer use adhesives, which can give off harmful gases into the cabin, particularly at high temperatures.
How can you tell if a cabin air filter is functional?
If the blower is set to maximum yet hardly any air comes through the vents, then it is definitely time to replace the cabin air filter. The filter medium is clogged and no longer lets any air pass through. This creates high pressure, which can result in considerable damage to the entire ventilation system.
MAHLE filters receive top marks
MAHLE tests the dust holding capacity of newly developed filter media and geometries in a specially designed flow channel. The filter element is subjected to specific fine and coarse dust loads and various air resistance levels—over a simulated life cycle of 20,000 kilometres.
Conclusion: regular filter changes protect man and machine!
Cabin Air filters
Technical Messenger 01/2011 - Cabin Air Filters with Activated Carbon [PDF; 309 KB]