A Detailed Explanation of Air Filters inside Cars

The air filter inside a car can filter out dust, smoke, odors, allergens and other pollutants that enter the vehicle. Assuming the vehicle has good sealing - the Windows are closed, the roof is intact and the doors are closed normally, then this filter can prevent dirt from the outside from entering the vehicle. Just like any air filter, the air filter inside a car intercepts harmful substances in the outside air as it enters the vehicle. The in-vehicle air filter is integrated into the vehicle's ventilation system.

Most modern cars are equipped with HVAC systems featuring in-car air filters. Saab was one of the earliest car manufacturers to introduce this configuration, which has been equipped in the 900 model since 1979. Other car manufacturers soon followed suit, but at that time, this configuration was mainly limited to luxury brand cars. By the early 21st century, in-car air filters had become widespread in mainstream vehicle models. For example, the 2002 Toyota Camry was equipped with an in-car air filter. Although the in-car air filter is not a mandatory device for vehicles, it has become very common nowadays. It should be noted that the air filter inside a vehicle is completely different from that under the hood of an internal combustion engine car. The air filter under the hood only filters the air entering the engine to ensure that no debris or foreign objects enter the cylinder. If you have ever strolled in front of the air filter shelves in a home building materials store, you would know that for such a seemingly simple component, there are actually a wide variety of choices. The situation of the air filter inside the car is similar. The types and sizes of particles that the specific product can filter will be indicated on the product packaging. Generally speaking, the price of an in-car air filter will increase as its claimed filtering effect improves.

You can choose an affordable filter that can filter out some particles but still allow others to pass through. Medium-grade filters can filter out more particles, but they are not as good as top-grade filters. As the size of the filter varies by vehicle model, the choice of filter that suits your specific vehicle depends on the product that can be installed inside its filter housing. If the local auto parts store doesn't have the filter you want, you might consider searching online.

Some in-car air filters use activated carbon to better adsorb odors. Some filters also have a certain level of high-efficiency particulate air filtration function. To meet this standard, a HEPA-compliant filter must be capable of removing at least 99.97% of dust, pollen, mold, bacteria, and other airborne particles as small as 0.3 microns. Just like the air filter on the heating equipment at home, the interior filter of a car can be replaced, and there is a reason for this. As time goes by, the filter will gradually get clogged and dirty while performing its duties. Replacing a new filter helps ensure the air inside the vehicle is clean and enables the ventilation system to operate at its most efficient level.

The frequency of air filter replacement depends on many factors that vary greatly, including the usage frequency of the vehicle, the operating environment of the vehicle, and the quality of the filter used at that time. The car user manual will provide the recommended replacement frequency, and usually there will be two or more replacement schedules for you to choose from, depending on the vehicle's usage and location. These suggestions can be taken as guidance, but if you think they are appropriate, you can also make adjustments according to the actual situation. Unlike not replacing the engine air filter, using a dirty in-car air filter will not cause your vehicle's warranty to expire - but it may harm your lung health. That is to say, the prices of most in-car air filters are relatively low. Therefore, for the sake of your own health, it's better not to breathe dirty air while driving.

In addition to calculating the service life of the filter, there are also some signs that can help you determine whether it's time to replace the air filter in the car. If the air blowing out from the vent has an unpleasant smell, it is very likely a signal that the air filter in the car needs to be replaced. If the air volume of the ventilation system is not as large as before, or if there is noise when the fan is running, it is very likely that there is a blockage somewhere in the ventilation system - and a dirty car air filter is very likely to be the culprit.