Homeowners know that to keep the air conditioning functioning properly in their homes, they have to regularly change the filter(s), have the system serviced and checked, and keep the coils on the outside unit (the condenser) clean. Interestingly enough, cars are exactly the same!
If the A/C filter (or filters) in your car get too dirty, it can restrict the flow of air and can actually shorten the life of the blower motor by causing it to overheat. The blower delivers the volume of air through the vents in the dash. The air that comes into the dash is pulled from outside. The function of the filters is to catch debris and trash that are also pulled into the “Blower Box” and prevent it from coming inside the cabin of your car. This is especially important in keeping pollens and allergens from entering the cabin of the car.
Many cars have additional filters that also filter the “recirculated air” that is reused from the cabin of the car. You never really know how important these filters are until you actually see how dirty they become. The recirculation filters are particularly important if you carry pets and children in your car. We have found some situations where rodents have entered the filtering system and built nests because the filters were already so dirty, they took advantage of the “nesting material”.
The frequency for changing filters may depend upon where you live, the conditions and even the climate. Car Owner’s Manuals specify two types of service conditions: 1.) normal and 2.) severe. In “Normal Service Conditions”, the filters would be replaced once per year. In “Severe Road Conditions”, the filters would be replaced 2 to 3 times per year, depending upon the area. Dallas Texas is considered a Severe Condition.
Road construction, heavy traffic, lawn maintenance (leaf blowers), high activity in allergens such as dogwood and cedar, rural dirt or gravel roads, and city pollution are such some of the cases where cabin filters would need to changed more frequently. These filters should be part a of your regular service inspections and checked at least 2 times per year.