What is the Purpose of an Air Filter?

The role of air cleaners is to clean the air that circulates through your heating and cooling system. Air from the HVAC system passes through the air filter, trapping particles and contaminants such as dust, mold, pet dander, and fungal spores. The mesh, which is the main component of the filter, captures these materials while allowing air to flow freely. If you don't change the air filter regularly, the air won't be able to pass as easily and more particles will be able to pass through the mesh, reducing indoor air quality.

Air filters are also important for car engines. Clean air is necessary to prevent engine contamination and damage. An air filter acts as a barrier against harmful particles entering the engine. Dirty air can reduce engine efficiency and cause damage; an air filter prevents it.

Allergens such as dust and pet dander settle on carpets, surfaces, and bedding rather than circulating through the air. To manage asthma and allergy symptoms, it's best to use medium to high efficiency air filters with a portable air filter in the bedroom, along with regular cleaning. No matter what HVAC system you have, you need a quality filter that fits properly to keep indoor air quality clean and your unit operating at peak efficiency. According to MIL-STD-282, a true HEPA filter must capture at least 99.97% of airborne particles with a diameter of 0.3 microns.

Oil bath air filters were widely used in automotive and small engine applications until paper filters became more popular in the early 1960s. It's also a good idea to change your air filter more often if you live in an area with high pollen content. Engine air filters should be replaced between 15,000 and 30,000 miles depending on vehicle type and driving conditions. However, it's recommended to replace your air filters every 12,000 to 15,000 miles (19,000 to 24,000 km) for maximum performance.

If you have a house with several inhabitants who could have respiratory problems due to a dirty air filter, buying a new filter every few months may be cheaper than having several people visit a doctor at once. Pleated filters trap and retain several grams of dust, preventing it from returning through the ducts and settling on surfaces in your home. In an ionizing air filter, dirty air passes first through a pre-filter and then through an ionizer to give airborne particles an electrical charge. Oil-moistened polyurethane foam elements are used in some car replacement air filters.

A clean, properly installed and working air filter increases engine performance and fuel consumption. If you're installing an HVAC filter in residential spaces, it's recommended to use one with a MERV rating of less than 13.