What Are Cabin Filters? How Do They Work?

Cabin air filters are an often-overlooked aspect of car maintenance, although they play an important role for the passengers sitting inside the vehicle. Today, I will give you an overview of cabin filters, their types, and the reasons you should regularly inspect and clean them for optimal performance. So read on:

What is a Cabin Filter?

A cabin filter is designed for your car’s HVAC (heating, ventilation, and air conditioning) system to keep the inside of your car clean and pollutant-free. You would definitely know that your car has an air filter that you regularly need to clean for the engine to run smoothly. Well, a cabin filter does the same job, but it protects your car’s cabin instead of the engine.

Most modern vehicles have a cabin air filter securely hidden behind the glovebox or dashboard. You can easily find out its exact location by referring to the owner’s manual if you are having trouble locating it otherwise. Alternatively, you can always ask a mechanic to have a look when you take your car to the workshop next time.

How Do Cabin Filters Work?

As mentioned earlier, a cabin filter pretty much works the same way as a regular air filter does for your car’s engine. It intercepts the particles and other pollutants present in the outside air before they enter the car. Without a cabin filter, all air entering your vehicle would be full of dust and allergens, thus affecting passenger comfort. With a cabin filter, your car’s interior stays clean for longer and the occupants don’t have to breathe unhealthy air while driving.

The pleated filtration material – which is made of paper, cloth or carbon – is mounted on a frame and placed in the ventilation system to filter the air coming through. It traps the dust, pollen, exhaust gases and particles in the air and specifically prevents these from entering the passenger compartment. Apart from open windows, all air enters your vehicle through its HVAC system. The cabin filter purifies the air supply going into the heating and cooling system to ensure passenger comfort while driving. As a result, when you turn on the air conditioning or heating system while driving, you get clean air free of dust and irritants.

Types of Cabin Filters

Cabin air filters come in a variety of materials, which determine their performance and benefits. When choosing a cabin filter, you need to decide if you simply want protection against dust particles and allergens, or you also wish to get rid of unpleasant odours. This may depend greatly on your environment and your living space. If you live in a densely populated area with lots of road traffic and pollution, I would suggest you invest in a good cabin filter. However, before selecting one, you must know whether a certain type of filter is compatible with your vehicle’s model. Let’s discuss the two main types of cabin air filters.

• Particle Cabin Filters

These are the standard cabin filters designed to prevent small particles from entering the vehicle. Particle cabin filters work great for filtering out debris, dust, mould spores or pollen. Some of these can even trap particles as tiny as 0.3 microns.

• Activated Carbon Cabin Filters

These products filter out particles the same way as regular particle cabin filters do. However, carbon filters have an additional layer, usually made of activated charcoal that also prevents different odours and harmful gases from entering the car.

Cabin Filters vs. Air Filters: What’s the Difference?

A standard air filter sits under the hood, and its job is to protect your car's engine by filtering the incoming air. It prevents dust and other particles from entering the engine. Cabin filters, on the other hand, are designed to filter the air flowing inside the vehicle (i.e. in the cabin). Some cars have cabin filters under the hood, while others have them behind the glove compartment or under the dashboard.

Why Do You Need to Keep Your Cabin Filters Clean?

A dirty or clogged cabin filter cannot do its job effectively, allowing environmental pollutants to enter your car. Apart from causing passenger discomfort, the dirty filter will also affect the efficiency of the car’s heating and cooling system. When you turn on the AC or heater, you will notice the cooling or heating is not up to the mark, which indicates the filter is dirty. You should always make sure that both the air filter as well as the cabin filter are clean for a comfortable drive.

Regular inspection and cleaning of the cabin filter is a vital part of overall vehicle maintenance. You don’t want to cause discomfort to yourself and your fellow passengers when you go out for a drive. One way to ensure that is by providing them clean air for breathing. Any passenger with certain allergies to dust or pollen would not enjoy a ride if they constantly sneeze in your car, and neither would you. Hence, it is vital to keep your car’s cabin filter clean and replace it when necessary. Experts recommend changing it after 25,000 to 50,000 km drive. However, it is wise to check your owner’s manual for the recommendation.