Keeping your homes HVAC running at peak efficiency is paramount as a home owner, and knowing the types of HVAC filters available and save you thousands in time and money. Your heating and cooling system’s filters play an important role in clearing the air of dust, dander, pollen, and other small, potentially irritating particles. Each filter traps these so the air in your home remains clean. These filters stop particles from recirculating; preventing contaminants from building up in the HVAC system, which can cause serious damage.
While having a filter is critical, it’s also important to know the best HVAC filter for your system and home. Here’s a look at the different types of HVAC filters to help you better understand the advantages of each.
MERV Ratings Explained
| MERV Rating | Average Particle Size Efficiency in Microns |
| 1-4 | 3.0 – 10.0 less then 20% |
| 6 | 3.0 – 10.0 49.9% |
| 8 | 3.0 – 10.0 84.9% |
| 10 | 1.0 – 3.0 50% – 64.9%, 3.0 – 10.0 85% or greater |
| 12 | 1.0 – 3.0 80% – 89.9%, 3.0 – 10.0 90% or greater |
| 14 | 0.3 – 1.0 75% – 84%, 1.0 – 3.0 90% or greater |
| 16 | 0.3 – 1.0 75% or greater |
Learn the Different Types of HVAC Filters
High Efficiency Particulate Air (HEPA) Filters
HEPA filters, according to the U.S. Environmental Protection Agency, filter out 99.97% of airborne particles down to 0.3 microns in size.1 But they can trap particles that are larger or smaller. A HEPA filter can screen out dust, pet dander, mold, pollen, and even bacteria and viruses.
The filter’s performance is measured with a Minimum Efficiency Reporting Value, or MERV. Filter MERV ratings go from 1 to 16. For the best filtration/efficiency, look for MERV 11 or higher ratings. While higher rated filters offer the most protection, they are also denser and can restrict air flow.
Fiberglass Air Filters
Inexpensive and disposable, fiberglass filters are the least straining on HVAC systems, and are thus one of the most common types of AC filters. They keep large particles out but are not that effective at filtering dust and other smaller particles. In other words, they’re not the right option for preventing or alleviating allergies. Fiberglass filters typically have a low MERV rating of around 4.
Pleated Air Filters
Highly effective at filtering out smaller particles, even more so than fiberglass. A pleated filter is usually made of cotton or polyester folds; the more pleats, the better the product is at filtering out dust and particulates like pollen and mold spores. Pleated air filters typically have MERV ratings of 5 to 8 (some go as high as MERV 13). They offer slight improvements to indoor air quality and, while being longer lasting and recyclable, can reduce HVAC efficiency.
UV Filters
Ultraviolet, or UV, lamps are installed in the HVAC unit. The UV radiation is highly effective at killing microorganisms and destroys bacteria and viruses. However, UV filters aren’t as good at capturing dust. Therefore, these filters are often installed along with HEPA or other filtration options. One downside is they can emit ozone, which can have effects ranging from coughing to respiratory disease.
Electrostatic Filters
An electrostatic charge generated by small cotton and paper fibers attracts dust and airborne particles. Electrostatic filters can be disposable, but some are reusable so you can clean and reuse them, saving on buying a replacement every time. They’re generally effective for smaller pollutants, but larger particles may not be captured sufficiently, leading to respiratory symptoms.
Media Filters
Media filters provide the benefits of a high surface area and MERV ratings without increasing static pressure or restricting airflow. Captured particles are sealed in the filter so they won’t get rereleased and recirculated. These types of filters can last longer; you might need to change them once or twice a year, so the maintenance overhead is lower.
Washable Filters
Washable filters in general are great if you’re looking for a reusable, long-lasting, and environmentally friendly option. While the initial cost may be high, the investment can last for years because you won’t need a new filter every few months. Just be sure the filter is dry before reinstalling it, as mold and mildew can otherwise grow in a moist medium.
Contact Sky Heating & Air Conditioning
Our experienced technicians can install, replace, or repair your AC unit in Portland and surrounding areas. Any HVAC issue can be addressed, from changing or selecting a new filter to component replacement and HVAC duct repair. For more assistance regarding the types of HVAC filters or obtaining the service you need, get in touch with us online or call 541-275-2918 today!