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How Often Should You Change Your HVAC Air Filter?


Your heating and cooling equipment depends on a number of different parts to work properly. However, of all the various components, the one that may have the single greatest impact on the functionality of your system as a whole is your air filter. Your air filter is positioned between the fan which pulls air into your system and the air return vent, enabling it to strain the air in order to remove dust, pollen, hair, dander and other floating debris. This not only improves your indoor air quality, but also prevents a number of issues including reduced cooling capacity, air conditioner freezing and more.

Despite the fact that air filters are cheap and easy to get, (generally going for just a few dollars at your local home improvement store), the overwhelming majority of homeowners donandrsquo;t replace their air filter nearly often enough. There are plenty of reasons for this, but the simplest and most common one is because homeowners just donandrsquo;t know how often they should change their filter or how to check for it. So to help, this blog has some valuable and practical advice for how often you should change the filter in your HVAC system.

Average Filter Lifespan

Every filter is going to have a different practical lifespan. A filterandrsquo;s thickness, material, number of pleats or folds, and actual filtration strength all influence how long it can be expected to work at a reasonable capacity. However, the most common types of air filters in most homes can generally be expected to last about three months before they will need replacement.

However, that number can go up or down with usage. For example, if you run your HVAC systemandrsquo;s fan throughout the day on most days, even without using your air conditioner or furnace, your system will continue to pull air through your air filter, and that will drastically shorten its lifespan. Those who use their air conditioner or furnace sparingly and only turn it on in the most frigid or sweltering of temperatures may not have to replace their air conditioner for six months or more.

Likewise, thicker filters can last longer, as they have a great amount of filtering media to allow air to pass through. Pleated filters, or those that have folds throughout them, can often capture even more dust and debris before needing to be replacedandmdash;a factor that often makes up for their more expensive price tag.

Does Your Home Have Any of These Filter-Clogging Factors?

The quality of your indoor air is also a huge factor in how often you should change your indoor air filter. Do you know whatandrsquo;s in the air youandrsquo;re breathing? You may be surprised to learn just how bad indoor air can be. According to the EPA, concentrations of certain pollutants are often two to five times higher indoors than they are outside. And depending on what you do or what you have in your home, that number can certainly apply to you.

For example, if you smoke inside in your home, the air is likely full of so much more than just smoke odors. Smoke also releases smoke particles and other air pollution into the air which can have detrimental health effects - the reason why “secondhand smokeandrdquo; is such a dangerous issue for young children. Dogs and cats release fur, pet dander and other allergy-causing pollutants into the air. Even homes with more people in them are more prone to filling up their air filter faster, requiring more frequent changes than someone who lives alone in a small apartment.

Check Your Filter Every Month

Whatandrsquo;s the best way to tell that itandrsquo;s time to change your air filter? Simply check it every month. Find your indoor unit and slide the access panel off which conceals your air filter, pull the filter out, and check the side that faces your air return duct. If the filter appears clean or has just a slight discoloration from use, then itandrsquo;s okay to leave it for another month. However, if itandrsquo;s turning a distinct shade of gray then itandrsquo;s time to swap your filter out. Do this before your filter gets too dirtyandmdash;a dirty filter can cause a number of different problems with your system and itandrsquo;s not worth paying for a major repair when the cheap and easy process of swapping an air filter would have prevented it.

If you need your air conditioner and furnace maintained or repaired, call Valley Heating, Cooling, Electrical and Solar at (408) 868-5500 today.

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