HVAC System Filters 2018 GuidePublished on: October 18, 2018
What Filters are Best for your Home and your HVAC System?
The filter is an integral component of your HVAC system. It keeps your heating and cooling equipment running efficiently and moving air properly, protects it from damaging debris, and helps everyone breathe easy.
The right filter for your equipment depends on the type of HVAC system you have as well as the indoor air quality needs of your home. Our HVAC System Filter Guide will help you make an informed choice when it comes to filter purchases.
Types of HVAC System Filters
Filters for central HVAC systems, including furnaces, heat pumps, and air conditioners, are either disposable or reusable.
Reusable filters can be cleaned and reinserted into the system whereas disposable filters must be replaced on a regular basis. Your owner’s manual will indicate whether your HVAC system operates with a reusable or disposable filter.
Common types of HVAC system filters include:
Fiberglass or Synthetic Filters
These filters are made from fiberglass or other synthetic materials and trap contaminants as air passes through. Fiberglass or synthetic filters are typically lower quality, lower cost and disposable.
Polyester filters are a disposable filter option using polyester material to trap airborne particles. These filters offer a higher level of filtration compared to fiberglass options.
Electrostatic filters are made up of self-charging fibers, attract airborne particles and trap them within the filter material. Reusable or disposable options are available.
Pleated filters use a pleated media and trap airborne contaminants on its surface. They are more efficient and offer a longer useful life than fiberglass filters.
High-efficiency particulate air (HEPA) filters are the most efficient option available and provide superior contaminant removal. Because the filtration is so strong, these filters can hinder airflow and are not appropriate for all homes.
HVAC System Filter Ratings
All types of HVAC system filters are rated for their efficiency in removing airborne particles. MERV is the rating used and stands for minimum efficiency reporting value. MERV ratings for residential filters range from 1 to 16. The higher the number, the higher the efficiency of the filter.
MERV 1 to 4
These filters control contaminants above 10 microns in size. They are effective for removing larger particles of pollen, dust mites and some fibers. Fiberglass and synthetic, electrostatic and washable filters are available with this rating range.
MERV 5 to 8
These filters effectively capture particles between 3 to 10 microns. This includes mold spores, fine dust such as cement or pudding mix and hairspray particulates. Disposable pleated and fiberglass or synthetic filters are available in this rating range.
MERV 9 to 12
These filters capture particles between 1 and 3 microns, including Legionella, lead dust, humidifier dust, milled flour, welding fumes and automobile emissions. Disposable polyester and pleated filters are available in this rating range.
MERV 13 to 16
These filters effectively capture contaminants down to 0.3 microns in size, including bacteria, tobacco smoke and sneeze droplets. Fiberglass, pleated and HEPA filters are available in this rating range.
Filters for Other HVAC Systems
Some HVAC systems use different filters. Ductless mini-split heating and cooling systems typically use an air filter within each indoor air handling unit. These filters are often reusable, while disposable filters may be available depending on the model.
Air purifiers or air cleaners use filters as well, with the type varying based on the type of indoor air quality HVAC system. HEPA filters, activated carbon filters, charged media filters, antibacterial filters and electrostatic precipitators are all filter options for different types of air cleaners.
Humidifiers and dehumidifiers also use filters. A dehumidifier filter cleans impurities from the air needing moisture control. A humidifier filter captures pollutants and minerals from the water used in the humidification process.
These filters may be disposable or washable – the owner’s manual will tell you the type of filter within the system and instructions for its care.
Find Help for Your HVAC System
Get the expert help you need to make the right filter decision for your home and HVAC system. Use AC Southeast® to locate a quality local heating and cooling company for filter questions specific to your home.