Main Air Filter Types
Your home’s indoor air quality is an essential part of your quality of life. If you or someone in your home has respiratory problems, it becomes a necessity. Using the proper air filter for your home’s heating and cooling system makes all the difference. If you’re dealing with stuffy air, it’s time to explore the different types of air filters for improved indoor air quality.
There are seven main types of HVAC filters, each with its advantages and disadvantages. Which one you choose has a lot to do with what you want for your home.
But before we dive into the different types of air filters you can use in your HVAC systems, let’s take a closer look at how to determine a filter’s level of protection from airborne particles. Armed with that knowledge, you’ll be better equipped to compare the air filters.
How Types of AC Filters Influence Indoor Air Quality
Thanks to the minimum efficiency reporting value (MERV) rating, any filter with the same rating produces the same filtration quality. The minimum efficiency reporting value is a consumer standard developed by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE). MERV measures a filter’s ability to capture small particles ranging from 0.3 microns to 10 microns. The higher the MERV rating, the more efficient and effective the filtration is. A low MERV rating, regardless of filter type, will provide lower filtration.
Though MERV ranges from 1 to 20, the ideal range for a home is from 8 to 13. If you go lower, you won’t be able to capture particles to clean the air. Any higher than that, and you’ll force your home’s heating and cooling system to work too hard to filter everything. Too much of this, and your HVAC won't last as long as it should.
That said, MERV isn’t the only air filter rating system out there. It is, however, the only consumer standard. Home improvement stores have created their own ratings that are similar to MERV but are not standardized. To learn more, read: FPR vs. MERV vs. MPR .
Since all filters with the same rating provide the same filtration level, why does the material they use matter? Some air filters will last longer than others based on the filter's surface area and the filter's thickness. Some will cost more than others. It comes down to what works best for your home’s needs, budget, and what your HVAC professional recommends.
Fiberglass FiltersThese are the most common types of air filters. Why? Because they are among the most affordable options on the market today. It's made with strands of fiberglass. They are highly effective at protecting your HVAC system from dirt and debris. They aren’t a good option for cleaning the air. They can’t strain many airborne contaminants.
Advantages of Fiberglass Air Filters
- Price: A fiberglass filter is one of the cheapest options out there.
- Effective: When it comes to dust and lint, these air filters do a great job.
Disadvantages of Fiberglass Air Filters
- Not an air purifier: These aren’t great at capturing the smaller particles. This means they don’t do much to clean your air. Ultimately, they just protect your HVAC system.
- Not the best for breathing issues: If someone in your home lives with allergies, asthma, consider another kind of air filter.
- Easily clogged: These filters can easily clog with dirt, dust, and other debris. Change them regularly to keep enough airflow moving through your system.
Pleated Air Filters
Pleated filters are made with cotton or polyester fabrics folded multiple times to create pleats. You can find these with a MERV rating between 5 and 13. They are effective at filtering dust along with other airborne pollutants. Like fiberglass filters, they don't do a good job at filtering the air. They are less resistant to airflow.
Advantages of Pleated Air Filters
- Better filtration: A pleated filter has more surface area to allow for better filtration. The more pleats the filter has, the better filtering it will do. Pleated filters are good at handling things like mold spores and pet dander.
- Flexible options: You can find these filters and reusable and disposable options. They help to reduce the noise of your HVAC fan.
- Replace less often: Pleated filters last longer than most fiberglass filters. They are known for their superior dust-stopping ability. Though they're more expensive, you don't have to have a new one every month. It’s possible to recycle used filters.
Disadvantages of Pleated Air Filters
- Pricey: Pleated filters are expensive.
- Reduced Airflow: Your system has to work harder to pull air through the unit. Over time, this may mean your home's air conditioning system loses efficiency.
High-Efficiency Particulate Air (HEPA) Filters
HEPA filters are those with a MERV rating of 16 or higher. Most homes don’t need this level of protection. They can remove at least 99.97% of airborne particles, including mold and other allergens as tiny as 0.3 microns. They can remove the smallest particles, including cigarette smoke, bacteria, and other pollutants.
- Effective at cleaning the air: HEPA filters are a great way to clean air inside your home. They attract incredibly small particles, ensuring it’s easy to breathe.
- Cost-effective: It can be years before you need to replace one of these, making them a cost-effective option over the long term.
- Must be adjusted specifically to your HVAC system: Generally speaking, anything higher than a MERV 13 makes your system work too hard to filter the air. That’s why a contractor has to adjust them specifically to your HVAC system - and they’re only recommended for those with severe breathing problems.
- Can’t protect against everything: Odors, fumes, and gasses are no match for HEPA air filters. Some pollutants may stick to the filter, leading to mold growth, and the need to replace the filter sooner.
- More expensive upfront investment: Even though it may be years before you need to replace a HEPA filter, they are more costly at first compared to different types of air filters.
Ultraviolet Light Filters
UV filters use a shortwave UV light to kill bacteria and viruses. As air passes through your HVAC, the UV lamp disinfects using germicidal radiation. This type of filter is excellent for killing microorganisms that may harm your health such as mold.
That said, there is potential for UV filters converting oxygen into ozone. Small amounts of ozone can cause residents to experience chest pain and develop a cough. Higher amounts can be worse than existing respiratory problems like asthma, which could be a risk for those with certain health conditions.
Advantages of UV Filters
- UV light: Kills small particles of harmful pollutants like germs and mold. The resulting indoor air quality is wonderful for those with respiratory issues.
Disadvantages of UV Filters
- Expensive to install: These HVAC filters must be professionally installed.
- Ineffective against larger particles: These filters can’t get rid of more common irritants like dust mites and pet dander. They’re also ineffective against tobacco smoke and other odors. That’s why they’re often installed alongside your existing filter.
Media HVAC filters have more benefits than standard filters with high MERV ratings. Media filters offer the same level of filtration as a highly-rated MERV filter. They get the job done without affecting airflow or static pressure. These have a greater surface area to provide high-quality filtration while also preventing static pressure.
They're easy to maintain and great to combat bacteria and other particles. The filtered contaminants are sealed into it which prevents it from being pushed back into the home.
Advantages of Media Filters
- Low Maintenance: These only need to be changed once or twice a year.
- Excellent filtration: Large surface area means they can filter out many harmful particles.
Disadvantages of Media Filters
- Not a self-service option: Media filters have to be professionally installed.
- No odor protection: They are not effective against odors.
Electrostatic filters use a mixture of fibers to create static electricity. This helps to attract particles of dust and dirt. The magnetism of the electrostatic charge keeps the particles from scattering through the home. It is a great choice for people who need to combat allergens.
These are available as disposable and reusable. When it's time to replace your filter, you can either wash and use it again or throw it away and get a new one.
Advantages of Electrostatic Filters
- Cost-effective: These are affordable. You can cut costs with reusable ones because you don't have to buy replacements.
- Effective at improving air quality: They can remove most pollutants from your air.
Disadvantages of Electrostatic Filters
- May struggle with large particles: They do a great job with small pollutants. But when it comes to dust and mold spores, they aren't as effective. This is a bad option for people with breathing problems.
Some types of air filters are available as either reusable or disposable. Washable filters are not only a great way to cut costs but can help the environment as well. Though you'll spend more money initially, the investment ends up being cheaper since they last for years. All you have to do is wash and reuse it as needed rather than replacing it with new ones a few times a year.
It is crucial to properly maintain your washable filter so that they function as intended. Follow the instructions closely. You have to be sure you let the filter dry completely before placing it back into your HVAC system.
Even a small amount of water can lead to mildew and mold. Those particles are sent into the air you're breathing.
These filters have a lower MERV rating. They are a good option for people who don’t require specialty options.
Advantages of Washable Filters
- Save money: With the proper care and maintenance, you can use one filter for the life of your HVAC system.
- Environmentally friendly: One filter means less waste.
Disadvantages of Washable Filters
- Not an option for allergy sufferers: If it’s not completely dry, it can introduce allergens.
- Ineffective against odors: It can handle dust, dirt, and other contaminants, but won’t help with odors.
Breathe Easier with Filter King
Air filters play an important role in indoor air quality. That’s why we make it so easy for you to find the best filtration for your needs. We carry a variety of filter sizes and can accommodate custom orders, so you have what you need. We offer a variety of options, including carbon filters to protect against odor. Cleaner air isn’t far away. Need help finding the right filter size? We've got you covered.