No matter the type of HVAC system you use, you need to change the filter on a regular basis. Keeping the filter clean not only improves indoor air quality but also helps the heating and cooling systems perform better thanks to enhanced airflow. The question is, should you change the filter once a month? The answer depends on several factors. Understanding these factors and how air filters work is key to helping you determine how often to change yours.

What Is the Purpose of the Air Filter?

Improving indoor air quality is the main purpose of air filters for HVAC systems. These filters capture and hold airborne particles, including pollen, dust, pet dander, mold spores and other pollutants. They make indoor air cleaner and healthier by removing these harmful contaminants, which in turn reduces the likelihood of respiratory problems and allergies. On top of that, they shield the HVAC system’s parts from debris accumulation, which keeps them in top shape and extends their life span.

What Are the Different Types of Air Filters?

One of the major factors that impacts how often you should change your air filter is its type. Some HVAC systems are compatible with different types of filters, but some aren’t. You’ll need to identify the type of air filter in your HVAC system to ensure you replace it with the right one.

Pleated Filters

In a pleated filter, a metal or cardboard frame encases a synthetic fabric or paper medium. In comparison to flat panel filters, they provide a greater surface area for particle collection thanks to their pleated shape, making them more efficient. You can see how well they are at capturing airborne particles by looking at their minimum efficiency reporting value (MERV) rating. A MERV rating between eight and 13 is generally sufficient for most homes.

Air quality, use and MERV rating are a few of the variables that determine how long a pleated filter will last, but in general, they last anywhere from 60 to 90 days. Unless there is noticeable dirtiness or a substantial reduction in airflow, you may not have to change this type every month. Instead, once every two to three months should suffice.

Fiberglass Filters

A fiberglass filter consists of a cardboard frame that encloses layers of spun fiberglass fibers. These filters are budget-friendly and designed to catch larger particles like lint and dust, but they may not be able to catch microscopic allergens. If you have pets or someone in your house suffers from allergies, you should probably change a fiberglass filter at least once a month since they get dirty easily and require frequent replacement.

HEPA Filters

HEPA filters work really well at capturing tiny particles in the air. Their tightly packed fibers help them filter particles as small as 0.3 microns, which is particularly useful for those with allergies or respiratory issues. These filters last a lot longer than most other filters. In most homes, you only have to change a HEPA filter once every six to 12 months.

Ultraviolet Filters

Ultraviolet (UV) filters are another type of filter that you don’t have to mess with changing once a month. To eliminate mold spores, germs and viruses from the air, UV filters employ ultraviolet-C radiation. Their primary function is to reduce the development of microbes on HVAC system components and improve the quality of the air inside the home. Replacement of the UV bulbs in these filters is usually necessary after nine to 12 months.

Activated Carbon Filters

Activated carbon filters remove gases, smells and volatile organic compounds (VOCs) from the air using a layer of activated carbon granules. Their ability to lower chemical pollutants and unpleasant odors helps them do a good job of enhancing the air quality within the home. Despite its excellent longevity, you usually only need to change an activated carbon filter every three to six months. Nevertheless, variables like air pollution and odor levels could affect how often you need to change them.

Flat Panel Filters

A flat panel filter is a simple, low-cost filter that consists of a sheet-like arrangement of fiberglass or polyester fibers. Despite their use in HVAC systems, their filtering effectiveness is inferior to that of most other filters. To keep airflow sufficient and avoid dust accumulation, you need to change flat panel filters at least once a month, especially if you have pets in the home. The cost of replacing these filters might add up quickly since you have to buy new ones every month.

Washable Filters

The long-lasting materials used to make washable filters, including plastic or aluminum, make them ideal for repeated cleanings and reuse. You can rinse or vacuum them to eliminate built-up dirt and debris, making them a more sustainable option than disposable filters. The recommended cleaning interval for washable filters is once every one to three months. However, this might vary with use and environmental factors. To keep mold and germs from growing on these filters, you must clean and dry them properly each and every time.

Electronic Filters

Electronic air filters charge airborne particles using electrostatic precipitation or ionization, which then attracts them to the filter’s oppositely charged plates. Although they are great at catching tiny particles, they can create ozone in the process. To keep the collecting plates of electronic filters clean, cleaning is necessary at regular intervals. Depending on use and air quality, the recommended cleaning intervals usually range anywhere from once every one to three months.

Factors That Affect Replacement Intervals

There are several main factors that influence how often to change the air filter in your home’s heating and cooling systems. Understanding these factors will help you make an informed decision when it comes to replacing or changing yours.

Indoor Air Quality

You should change your filters more often if the indoor air quality is poor. It may also be necessary to replace the filter more often if you live near construction sites or in locations with high levels of pollution.

Pets

Homes with pets almost always require more frequent air filter replacements. This is especially applicable to homes with pets that shed a lot. The pet dander and hair in the air can quickly clog air filters.

Allergies

If you suffer from allergies or asthma, you may want to keep the filter changed on a monthly basis. This will help keep pollen and other harmful airborne pollutants to a minimum.

Home Size

How many airborne particles and contaminants there are in your house is proportional to its size. To keep the air inside a smaller house at an ideal level, it may not be necessary to replace the filter as often as in a larger home. Frequently checking the filter and monitoring its condition is the best way to know when to change it.

Evergreen Heating & Air LLC makes it easy to determine when to change your air filter. Some of the many services that we offer in Mooresville, NC, are AC maintenance, duct and vent cleaning, air purifier installation and mini-split repairs. We even offer a Comfort Care Club. Contact us today to speak with an HVAC expert about your air filter and how often to change it.

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