Frequently Asked Questions – Cabin Air Filters

• What is a cabin air filter?

  A cabin air filter is a panel style, pleated air filter designed to filter particles and airborne contaminants entering the cabin of the vehicle through the climate control system.

  Cabin air filters first emerged in European vehicles in the 1970s but are now found in nearly every modern vehicle.

• What does cabin air filter do?

  By removing harmful particles and gasses from the air, the cabin air filter keeps the cabin air clean and fresh for passengers while also protecting the delicate components of the car’s climate control system.

• What is the difference between a particulate cabin air filter and a carbon media cabin air filter?

  A particulate media cabin air filter is the most basic type of cabin air filter and can usually be easily identified by the white media that is used to make them. This white media is made of electrostatically charged fibers that attract and hold dust like a magnet. While effective in removing dust and other particles from the air, a particulate media cabin air filter does not neutralize odors.

  A carbon media cabin air filter is a more advanced filter that is usually grey in color and noticeably heavier than a white particulate media filter. Carbon media cabin air filters get the grey appearance from a layer of media that is infused with activated charcoal– It’s this unique layer that helps to eliminate bad odors from the climate control system before they get into the cabin.

• What is the difference between an engine air filter and a cabin air filter?

  A cabin air filter cleans airborne contaminants from the air circulating inside the cabin of the car. 

  An engine air filter serves a similar purpose, but in a completely different place. The engine air filter is positioned in the air intake system of your car’s engine and cleans dust particles from the air before they can get into your engine and cause damage.

• How often should a cabin air filter be changed?

  Original equipment manufacturers recommend changing the cabin air filter at varying frequencies– usually between 12,000 and 15,000 miles.

  However, it is critical to pay close attention to driving habits, climate, and the region where the vehicle is driven. Vehicles driven in arid environments should have the cabin air filter replaced with more frequency because the amount of dust in the filter builds up much quicker. In these situations, a filter may only last a month. In places where the temperature fluctuates greatly from season to season and a lot of debris falls off the trees, it’s recommended to change the cabin air filter at least twice per year– Once in the Spring and once again in the Fall.

• How will I know when it’s time for a new cabin air filter?

  The most common signs of a dirty or clogged cabin air filter are unusual smells in the cabin (especially if the smell gets worse when the heat or air conditioning are turned on) and decreased airflow through the dash vents.

• Does the cabin air filter affect the performance of the AC in the car?

  Absolutely! If the cabin air filter is very dirty it can severely diminish the AC performance in any car. Clogged cabin air filters also affect heat, defrosting, and defogging ability in certain weather situations. Failure to replace often enough can turn into a safety issue if windshield defogging is impacted.

• Can a dirty cabin air filter cause damage to my climate control system?

  In part, the job of a cabin air filter is to protect the delicate components of a vehicle’s climate control system. So, yes, a dirty filter can cause damage and it’s most often to the blower motor found within the system. In this case, failure to maintain the cabin air filter can turn into a very expensive ordeal.

• What is the airflow direction arrow on the side of the cabin filter?

  Premium cabin air filters like PUREFLOW are engineered for maximum airflow so your climate control performs it’s best. The arrows on the side of cabin air filters indicate the direction that air should flow. This is important because one side of the media features larger pores, allowing in as much air as possible. The other side has smaller pores, allowing enough air to get through to maintain adequate flow, while trapping airborne particles.

• How do I figure out which way the air is flowing in my climate control system?

  Verifying the direction of the flow of air is an important step when installing the cabin air filter because if it’s installed backwards, it will drastically restrict the flow of air and cause the filter to become occluded much faster than normal. In order to do this, simply turn on the fan and set the dial to max once you’ve removed the dirty filter. Then hold a piece of paper inside cabin filter housing and watch which side the paper moves to. When installing the new filter, make sure the arrow points in the direction of where the paper moved.

• How to I know the intended airflow direction of my new cabin air filter?

  Like most other cabin air filters, PUREFLOW cabin air filters feature arrows that indicate which way air should flow through the filter. In the extremely rare event that the arrows are missing you can use the colors of the cabin air filter as a guide like the arrows. The blue side of the filter is the clean side, so it should be pointed in the same direction as the airflow. The grey side is the dirty side, and it is meant to capture all the dirt in the air, so you’ll want to point the grey side against the flow of air.