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Joe W Fly Co HVAC Filtration 101

November 14, 2020

HVAC Filtration 101

We will discuss the what HVAC Filtration is and how it can improve your living and working environments.

Joe W. Fly Co., Inc., is placed among the most trusted providers of filtration solutions for commercial, institutional, industrial buildings and facilities.

What is HVAC Filtration?

HVAC filtration refers to the process of removing airborne particles, contaminants, and pollutants from the air circulated by a heating, ventilation, and air conditioning (HVAC) system. It involves the use of filters within the HVAC system to trap and remove various particles and pollutants, improving indoor air quality and ensuring the efficient operation of the system.


The primary purpose of HVAC filtration is to protect the HVAC equipment and maintain its performance by preventing the buildup of dust, dirt, and debris on components such as coils, fans, and motors. Additionally, HVAC filters help remove airborne particles such as pollen, pet dander, mold spores, bacteria, viruses, and other contaminants that can affect the health and comfort of occupants.

There are various types of HVAC filters available, ranging from basic fiberglass filters to high-efficiency filters. The efficiency of a filter is measured by its Minimum Efficiency Reporting Value (MERV) rating, which indicates its ability to capture particles of different sizes. Higher MERV ratings generally indicate better filtration performance, but it’s essential to balance filtration efficiency with the system’s airflow requirements.


Regular maintenance and replacement of HVAC filters are crucial to ensure their effectiveness. Clogged or dirty filters can restrict airflow, strain the HVAC system, reduce energy efficiency, and diminish indoor air quality. The frequency of filter replacement depends on factors such as filter type, MERV rating, the presence of airborne pollutants, and system usage.

It’s worth noting that while HVAC filtration plays a significant role in improving indoor air quality, it may not address all air quality issues. Other factors, such as ventilation, humidity control, and source control (e.g., removing pollutants at the source), also contribute to maintaining a healthy indoor environment.


What is the best air filter for my home?

The best air filter for your home depends on various factors, including your specific needs, HVAC system requirements, and indoor air quality concerns. Here are some common types of air filters to consider (not in any order):

  • Pleated Filters: Pleated filters have a larger surface area and a higher particle-capturing capacity than fiberglass filters. They are more efficient at removing smaller particles and have a moderate cost.
  • Media filters: can be made from various materials, including synthetic fibers, polyester, cotton, or a combination of these materials. These filters are available in different MERV ratings, indicating their filtration capabilities. Higher MERV ratings generally indicate better filtration performance.
  • Electrostatic Filters: Electrostatic filters use an electrostatic charge to attract and capture particles. They can be either washable or disposable. Washable electrostatic filters require regular cleaning to maintain their effectiveness.
  • Activated Carbon Filters: These filters have an additional layer of activated carbon that helps remove odors, smoke, and volatile organic compounds (VOCs) from the air. While they are not as effective at capturing particles, they are beneficial if you have specific concerns about odors or chemical pollutants.
  • High-Efficiency Filters: High-efficiency filters, such as HEPA (High-Efficiency Particulate Air) filters, have a higher MERV rating (typically 17-20) and can capture a wide range of airborne particles, including pollen, mold spores, pet dander, bacteria, and some viruses. These filters provide excellent filtration but can restrict airflow, so it’s important to ensure compatibility with your HVAC system.

When selecting an air filter, consider the following factors:

  • MERV Rating: Choose a filter with a MERV rating that suits your needs. Higher MERV ratings provide better filtration but may require a more powerful HVAC system.
  • Compatibility: Ensure the filter is compatible with your HVAC system’s requirements and dimensions.
  • Airflow Considerations: Filters with higher MERV ratings can restrict airflow, so check your HVAC system’s specifications to determine the appropriate balance between filtration efficiency and airflow.
  • Indoor Air Quality Concerns: If you have specific concerns such as allergies, asthma, or chemical sensitivities, consider filters that are designed to target those particular contaminants.

Consulting with an HVAC professional can provide valuable guidance in selecting the most suitable air filter for your home, considering your specific requirements and system capabilities.


How often should you change your air filter?

The frequency of HVAC air filter changes depends on several factors, including the type of filter, the MERV rating, the air quality in your home, and system usage. However, a general guideline is to inspect your air filter every month and change it as needed. Here are some factors to consider:


  • Filter Type: Different types of filters have varying lifespans. Basic fiberglass filters typically require replacement every 1 to 3 months. Pleated filters with higher MERV ratings may last longer, typically between 3 to 6 months. However, it’s essential to refer to the manufacturer’s recommendations for the specific filter you are using.
  • MERV Rating: Filters with higher MERV ratings have finer filtration capabilities, capturing smaller particles. While they provide better air quality, they can also become clogged more quickly, which may require more frequent filter changes. Be aware that a higher MERV-rated filter may also restrict airflow if not compatible with your HVAC system, so consult the manufacturer’s guidelines.
  • Air Quality: If you live in an area with high pollution, construction nearby, or have pets or smokers in your home, your air filter may become dirty more quickly. In such cases, you may need to change the filter more frequently to maintain optimal air quality and system performance.
  • System Usage: The more frequently your HVAC system operates, the more air is being filtered, and the more quickly the filter may become dirty. If your system runs continuously or if you frequently use your HVAC system, you may need to replace the filter more often.

It’s important to note that these are general guidelines, and individual circumstances may vary. Regularly inspecting the filter is crucial to determine when it needs to be replaced. A dirty or clogged filter restricts airflow, reduces system efficiency, and may even cause damage to the HVAC equipment. Ultimately, it’s best to consult your HVAC system’s manufacturer guidelines or consult with a professional to determine the appropriate filter replacement schedule for your specific situation.


Where can I buy  air filters?

You can buy air filters from various places, both online and offline. Here are a few options to consider:

  • Specialty air filter stores: Some stores specialize in selling air filters and related products. These stores may have a more extensive range of options and knowledgeable staff to assist you. Look for local air filter suppliers in your area or search online for specialty air filter retailers.
  • Home improvement stores: Retailers and hardware stores often carry a wide range of air filters for different HVAC systems. You can visit their physical stores or check their websites to browse and purchase air filters.
  • HVAC service providers: Companies that offer heating, ventilation, and air conditioning (HVAC) services often sell air filters as well. You can contact HVAC service providers in your area to inquire about purchasing air filters directly from them.
  • Manufacturer websites: If you know the brand and model of your HVAC system, you can visit the manufacturer’s website to find compatible air filters. Many manufacturers have online stores where you can purchase filters specifically designed for their systems.
  • Online retailers: Websites have a vast selection of air filters. You can search for specific filters based on your needs and order them online for delivery to your doorstep.

Remember to check the specific size, type (e.g., HEPA filters), and compatibility requirements for your HVAC system before purchasing air filters to ensure you get the correct ones for your needs.

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HVAC Filtration 101

HVAC Filtration 101

HVAC filtration refers to the process of removing airborne particles, contaminants, and pollutants from the air circulated by a heating, ventilation, and air conditioning (HVAC) system. It involves the use of filters within the HVAC system to trap and remove various particles and pollutants, improving indoor air quality and ensuring the efficient operation of the system.