How Does an HVAC Air Filter Work?

The HVAC filter is a crucial component of your home's heating and air conditioning system. It cleans the air just before it enters the fan and circulates through the ducts. As air passes through the filter, the material, usually cloth or pleated paper, traps any contaminants that are in the air. This helps to keep the system running efficiently and protects it from damage. When air enters the HVAC system, it is first heated or cooled and then pushed through the ducts that lead it to every room in the house.

Filtration generally occurs when spent air is returned to HVAC equipment for conditioning and distribution again. The air filter is placed at the point where air enters the system and traps particles as air passes through the fan. The main function of an HVAC filter is to trap airborne contaminants, not for air quality reasons, but to keep them away from the heating and cooling system. However, since the filter removes contaminants for the benefit of the system, air quality also benefits from their removal. To change the temperature in your home, the heating and air conditioning system draws air from a room, pulls it on coils to heat or cool it, and then blows warm air through the ducts to the other rooms in the house. When you clean the electrostatic air filter with a water hose, hold the filter so that you spray trapped particles outward rather than inward.

Dirty filters represent a disaster for heating and cooling equipment, home comfort and air quality. The opposite happens if you don't have an air filter or if your air filter is so dirty that it restricts air flow. Standard MERV values range from 1 to 16, and the number serves as an indicator of how well the filter will remove material from the air. Contrary to popular belief that air is cleaned to protect health, HVAC filters are primarily designed to protect the fan in your HVAC system. In recent years, this air-cleaning function has become more important for homeowners, and manufacturers have designed filters that use their heating and air system to remove microscopic particles such as dust, pollen, pet dander, bacteria, plant spores and mold, and even smoke from the air in your home. The efficiency level of HVAC filters will vary between different HVAC systems and different types of filters.

Air filters with a MERV rating of 14 or higher capture more particles, but they also restrict air flow more and clog up more quickly. So what are air filters used for? What does an air cleaner do in your home once it's installed? The main purpose of the air filter is to clean the indoor air so that it is healthier to breathe. Check with your trusted local HVAC service provider to see if an air purification system is right for you. Routinely changing or cleaning the filters in your home's heating and air conditioning system helps units work more efficiently and enjoy a longer lifespan. It's all too easy to skip a filter change when your HVAC equipment is hidden and out of sight, but this important task must become a priority. On the following pages, we'll discuss the function, types, classification system and routine maintenance of air filters in your home heating and air conditioning system.

If you follow this method and vacuum the filter at least once a month, you should have no problem keeping your electrostatic filter clean and working well.