The Dangers of Not Changing Your Cabin Air Filter

Just because a cabin air filter doesn’t directly affect whether your vehicle makes it from point A to point B doesn’t mean you should delay getting a new one — or not replace it at all. Changing your cabin air filter is an important part of regular vehicle maintenance and ignoring it can cause some pretty uncomfortable effects. Here’s why it’s important to regularly change your cabin air filter.

What is a Cabin Air Filter?

A cabin air filter shouldn’t be confused with your engine’s air filter, although they perform similar functions. Whereas the engine’s air filter ensures clean air gets to the engine, the cabin air filter stops contaminants such as dirt, dust, smoke, smog, pollen, mold spores, and exhaust gases from entering the cabin of a vehicle through the heating, ventilation, and air conditioning (HVAC) system. It also keeps out other debris, such as bugs, rodent droppings, and leaves.

Cabin air filters are typically rectangular and made of paper and a mix of other fibrous materials. They have pleats to better catch the contaminants. When air passes over the cabin air filter, debris is trapped by the filter and stopped rather than being pumped into the car. Eventually, that debris builds up, and the filter needs to be changed to continue to work efficiently.

What Happens if Your Cabin Air Filter is Dirty?

Dangers abound if you don’t replace your cabin air filter regularly. Here are a few of the risks a dirty cabin air filter poses.

Health troubles: A functional cabin air filter is essential in keeping the inside of a vehicle free of pollutants. A cabin air filter that’s dirty or clogged won’t filter those contaminants, causing problems for those who suffer from allergies or have breathing difficulties. A good rule of thumb is to replace your cabin air filter every February, before spring allergy season arrives, especially if you live in an area with a lot of trees. A new cabin air filter will prevent pollen from making its way into a vehicle and causing its occupants to start sneezing, or even worse.

HVAC system will run poorly: A cabin air filter left in place beyond its life span will make a vehicle’s HVAC system work harder, which can cause the motor to burn up. Dirty or clogged cabin air filters will reduce the amount of air flowing from the vents. That affects cabin air temperature, which depends on a steady flow of air passing through the heater core, evaporator or both components. Not changing your cabin air filter will make your HVAC system work much harder.

Poor window fog clearing: Another problem that arises when airflow is compromised is that windows won’t clear as quickly. Also, the diminished air quality that comes from a cabin air filter that’s overdue to be replaced allows condensation to form on the windshield. Once the cabin air filter is replaced, there will be less fog buildup on the windshield.

Foul odors: No, that terrible smell coming from your vents isn’t from anything that you just drove by. It’s coming from not changing your cabin air filter. Dirty or excessively clogged cabin air filters can produce a dusty, musty stench, especially when the HVAC system is turned on. Changing your cabin air filter at regular intervals will ensure that your passengers don’t have to wind down their windows in the dead of winter to get some fresh air.

Do You Need to Change Your Cabin Air Filter?

In a word: absolutely. So, what’s a good rule of thumb? Most manufacturers suggest swapping it out every 12,000 to 30,000 miles, depending on the specific vehicle. If you live in a heavily polluted area or routinely drive on dirt roads that kick up a lot of dust, you’d be wise to replace it even sooner. Allergy sufferers or those with compromised respiratory systems might consider getting a new one after as few as 5,000 miles.

How Much Does it Cost to Replace a Cabin Air Filter?

Replacing your cabin air filter can be a do-it-yourself task if you’re up to the challenge. In modern vehicles, most are located behind the glove box, beneath the dashboard or under the hood. While the cabin air filter is easy to access, be careful not to break any of the clips or pins holding it in. Cabin air filters typically cost between $15 and $50. If you can pull off replacing it yourself, you can save as much as $50 in labor costs.

Replace it regularly

Though your cabin air filter is out of sight, it shouldn’t be out of mind. By replacing it regularly, you ensure that the air circulating inside the passenger compartment of your vehicle is largely free of contaminants and that should be enough to make you breathe much easier.