What You Need to Know About HVAC Air Filters

Posted on Feb 12, 2020

Owning a home comes with plenty of responsibilities. You need to keep it clean and tidy, mow the yard, do the grocery shopping, etc. There are plenty of tasks involved in homeownership, but there is one that is often overlooked – HVAC maintenance. 

Properly maintaining your HVAC system will keep your indoor air quality at healthy levels. Before you get overwhelmed by the idea of taking care of an HVAC unit, though, we’re here to tell you don’t worry! To maintain your HVAC system, you just need to replace your air filter every couple of months.

Want to learn more about air filters? Below, we’ll go over everything you need to know so you’ll be an expert in no time!

close up of air filter screen

Types of filters

First things first, you need to understand the difference between the types of filters, as well as which one is best for your home’s needs. There are plenty of air filter brands on the market, but there are really only a few different types. Below are the most common:


Fiberglass air filters are the most common air filters on the market. They’re relatively inexpensive and work well to remove heavy contaminates and air particles. However, they’re not great at filtering smaller air particles. This is why they’re only great for homes that are pet-free and require only the most basic protection. On average, you can expect them to last about a month.


Pleated air filters are similar to Fiberglass but they have a pleated structure to them, in a V-shape. Pleated filters are considered relatively inexpensive with slightly better coverage than fiberglass. They last about 2-4 months.


Do you have pets in your home, or high allergies? Then a HEPA air filter might be the best fit for you. HEPA filters are capable of removing both large and small particles in your home’s air. The small particles that HEPA filters are known to filter out include bacterial, pollen, and mold.


These filters are the best option for people looking to protect their home from allergens. While slightly more money than other types of filters, HEPA filters last on average 3-6 months. 


Washable air filters are also known as permanent air filters. These air filters are great at reducing most pollutants in the air and only need to be cleaned once every 3 months for optimal usage. With proper care, they will work for about 5 years before needing to be replaced. Therefore, their higher price tag is worth it. 

Filter ratings

The next thing you need to know about air filters is the difference in filter ratings. These ratings may seem confusing, but they’re actually pretty straightforward. They’re referred to as MERV ratings and they are as follows:

MERV 1-4

These filters offer minimal protection because they’re designed to just provide minimal filtering and protection to the HVAC unit. MERV1-4 will remove pollen and dust but can’t remove smaller particles like bacteria. This filter is great if you have a low budget or you aren’t concerned about health problems. 

MERV 5-8

The next step up, MERV 5-8 offers a higher air filtration and is able to eradicate smaller mold and dust spores in addition to pollen and dust particles. The price on these filters in a little higher but it is still a budget friendly option.

MERV 9-12

MERV 9-12 is the next available option. It is able to capture much smaller particles than 1-4 or 5-8. These filters are able to remove pet dander, auto emissions, airborne articles, mold, dust, etc. This is great for people with allergies or respiratory issues because it keeps the HVAC unit clean of debris and build up.

MERV 13-16

MERV 13-16 is the highest quality filter on the market. These are often used in hospitals because of their incredible ability to remove large and tiny particles from the area. It can remove everything mentioned above, and also bacteria, viruses, etc. The cost is the highest of all filters but is really great for older people or those with high sensitivity to air quality. 


So you know what types of filters are available, and you know what their ratings are. Now, you should know about sizing. Air filters come in all different sizes, ranging from 10×20 all the way up to 25×25. Don’t stress out, though! There’s a simple way to know which size you need. Just check your HVAC unit. Yep, it’s that easy. Look on the side of the unit, or at the current filter, to determine the size you need.

When to change them

You know almost everything now, but there is one more question still remaining – when do you replace them? HVAC filter replacement varies per household, so it all depends. Don’t worry though, it’s easy to find out.  Just look at the filter guidelines and your lifestyle factors.

Filter guidelines

When you purchase a new air filter, there should be details on the packaging. This should tell you when your specific air filter will need to be changed out. Most air filters are anywhere between 1-3 months, but it’s best to take a look just to be safe. If you’re concerned you’re waiting too long between changes, just take a peek at it. If it looks dirty, then go ahead and change it out. Dirt signifies a lack of airflow, and that means the filter is not working as it should. 

Lifestyle factors

You should also be taking into account your lifestyle factors when determining air filter replacement. These factors include the following:

Air quality

If it’s smokey outside due to fires or the pollen/mold levels are pretty high, then chances are this will take a toll on your HVAC system, prompting you to change the filter more frequently. 


Do you have pets in your home? If so, you’ll probably find yourself changing the air filter more often. This is because the filter will be putting in extra work to remove pet dander from your air.

Ask for help

There you have it! You know everything you need to about air filters, including HVAC filter replacement! You can now shop for replacements and change your HVAC filter with ease. 


Not sure about air filters still? No problem! At AIRPRO Indoor Air Solutions, we are experts on all things HVAC. We’d be happy to help you understand more about your HVAC system.


Give us a call today, we can help you become an air filter expert in no time!

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