How Does An HVAC Air Filter Work?

The air filter is an essential component in HVAC systems, cleaning the air that flows through the system.

If an air filter is not maintained, it can affect other components of the system. Therefore, changing the air filters regularly is important to keep the system working optimally.

To keep your unit in tip-top shape, it’s important to know how an HVAC air filter works. 

What Is An HVAC Filter?

An HVAC air filter eliminates impurities in the air as it passes through the system before circulating through the ducts.

The filter is designed to trap contaminants such as dust, pollen, debris, and other small particles. This improves air quality inside the home. 

The air filter also protects the system by preventing pollutants from damaging the other components, prolonging the lifespan of the system.

One key indicator of the quality of the air filter is the Minimum Efficiency Reporting Value (MERV) rating.

Generally, air filters with high MERV ratings are thicker and denser than others, so they can purify the air of bacteria and other small harmful particles.

Hospitals typically use HVAC air filters of high MERV ratings to reduce the transmission of aerosols

Types Of HVAC Air Filters 

The ability of an HVAC air filter to trap contaminants depends on several factors, including the materials used in their construction.

For example, some air filters are made of thin material, while high-performance filters have multiple layers that offer better filtration. Here are different types of air filters for HVAC systems. 

Pleated Air Filters

These air filters are typically made from cotton or polyester that is arranged into folds to increase the surface area of the filter.

Pleated air filters are more effective in trapping contaminants due to the presence of the pleats. 

Fiberglass Air Filters

Fiberglass filters are also known as flat-paneled filters. These filters are inexpensive and may not trap smaller contaminants but can block relatively large contaminants from passing through. 

HEPA Filters

High-efficiency particulate air filters are one of the most effective air filters in the market that offer high levels of filtration. HEPA air filters can trap allergens, bacteria, viruses, and even smog in indoor air. 

UV Air Filters

When indoor air passes through a UV air filter, the UV rays kill microorganisms present in the air.

While this type of filter can effectively reduce the amount of microorganisms in the air, it may not be as effective in trapping dust or allergens as other HVAC air filters. 

Electrostatic Air Filters

These air filters are typically made from fiber or cotton. When air passes through it, it attracts contaminants by creating an electrostatic force. These air filters are reusable as they do not require replacements. 

How Does An HVAC Filter Work?

An air filter can be made from different types of materials, such as pleated paper, designed to trap pollutants from the passing air.

Choosing the right type of air filter can affect the performance, reliability, and longevity of the HVAC system.

The type of air filter is important, but equally important is the fit. You can use a cut to fit air filter to get exactly what you need.

HVAC filters use different technologies, but they all perform the same function of purifying the air of contaminants.

For example, some air conditioners have UV light filters that can eliminate living pollutants in the air, such as air-borne bacteria and mold.

A common type of air filter used in HVAC systems is the media filter, which effectively catches large dust particles that harm the system and pollute the indoor air.

Although these air filters are the most economical option, not be as effective in trapping allergens and other irritants as other air filters. 

High-efficiency particulate air or HEPA filters are highly effective in filtering out contaminants.

They are generally one of the best options for people with allergies or facilities requiring a controlled environment.

These filters are made of activated carbon material and fiberglass that removes small particles from passing through the system and recirculating indoors. 

There are also other kinds of air filters, such as electrostatic filters that capture contaminants through magnetism and washable air filters. However, these types of filters are less common. 

Do You Need An HVAC Air Filter?

Air filters not only purify the air inside your home, but they also improve efficiency – leading to reduced electricity consumption.

Even if the air quality inside your home does not require the addition of an air filter, you should still use one to help maximize the longevity of the HVAC system.

Without a properly functioning air filter, the HVAC’s components could get damaged, resulting in costly repairs.

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Author at Huliq.

Written By James Huliq