You naturally want clean air in your home. However, indoor air pollutant levels can be 2-5 times higher than outdoor levels. If you or a family member has allergies or asthma, a home filled with airborne particles like dust, dander, mold, or pollen allergens can be a real problem. In addition to regular cleaning and adequate ventilation, using an air purifier can help make your home as allergen-free as possible.

A common air purifier used to control the levels of airborne particles is the electrostatic air filter unit, which creates electrical fields to capture particles. Electrostatic air purifiers promise to attract dust and other particles in the air with a clever bit of electromagnetism. They can be used in portable air purifying devices or can be mounted into the ducts of residential HVAC systems.

What is an Electrostatic Filter?

Known as washable or reusable filters, electrostatic air filters are placed over a furnace, typically replacing a pleated filter. The primary purpose of any filter is to clean the dirty, outdoor air that is forced into your home.

What is an Electrostatic Filter

Electrostatic air filters use electricity to capture dust, pollen, and other airborne particles before they enter your home, setting them apart from pleated filters. These filters are used for both heating and cooling systems.

Benefits of Electrostatic Air Filters

Electrostatic air filter units, depending on the right conditions, remove many particles of a certain size from the air. However, it's important to weigh the benefits and drawbacks to decide if an electrostatic filter is right for you. Some of the benefits include:

  • Low Cost: An electrostatic air filter unit (whether portable or installed in your HVAC system) has a one-time initial cost. There is no need to replace any filter media since the devices do not come with filters.
  • Washable/Reusable: The collector plates within the device are washable and reusable. It's a long-lasting product.
  • Effective: Electrostatic filters with collector plates do a fairly good job of removing dust and other particles from the air, as long as the plates are kept clean. It completely prevents the formation of smoke and odors.
  • Save Time and Hassle: Not only do you save on filter costs, but you also save time by not having to search for the specific size of air filter you need in stores.
  • Efficient Operation: Electrostatic air filters have a MERV rating of about 5 or 6 depending on the brand (MERV stands for Minimum Efficiency Reporting Value), which means they consume low energy.
  • Good Air Filtration: These filters do a good job of filtering the air in your system, electrostatic air filters work to improve air quality compared to pleated filters.

Disadvantages of Using Electrostatic Filters

  • Lose Effectiveness if Not Cleaned: The efficiency of an electrostatic filter is highest when the collector plates are clean and not overloaded with particles. Experts recommend cleaning them at least once a month, if not every two weeks.
  • Only Remove Particulate Matter: Electrostatic air filters reduce the level of particles in the air such as dust, pet dander, and other allergens, but do not eliminate harmful gases in any way.

How Do Electrostatic Air Filters Work?

They might seem complex, but the real science behind electrostatic air purifiers is intuitive. Electrostatic air filters act like magnets for dust and other particles floating in the air.

Think about how the positive and negative sides of magnets attract each other. This principle is applied to the particles in the air and the plates inside the air purifier. If particles passing through a filter are given an electrical charge, and a few plates with opposite charges are placed next to them, the particles are drawn towards the plates and stick to them. Ideally, many of the particles floating in your home get trapped inside the device, reducing the indoor allergen problem.

Meanwhile, the same principle of electrostatic attraction is what causes your hair to stand on end when you rub a balloon on your head in dry conditions. The balloon strips electrons from your hair, giving the balloon a negative charge and your hair a positive charge. Your hair, being very light, is then attracted to the balloon and stands up.

Electrostatically Charged Fibers

You may be looking for the "electrostatic air filter" type, which is a reusable filter medium. These are filter panels made from fibers that are electrostatically charged materials. This refers to the filter medium and is distinct from the category of electronic air purifiers that use an external power source.

Unlike "pleated" filters like HEPA filters, electrostatically charged filters are considered "flat" filters. The difference lies in the fact that if the fibers are electrostatically charged, particles that come into contact with the fibers can be attracted and stick to the filter instead of being trapped inside the fibers (as in a HEPA filter).

An electrostatically charged panel filter is typically installed directly into your HVAC system and is made from coarse fibers. Dust and other particulate pollutants passing through the filter in your home can be attracted to and adhere to the fibers.

Electrostatic Air Filter Maintenance

It is crucial to clean these washable filters monthly to avoid any sudden malfunctions. Following the cleaning steps ensures maintenance is correctly performed.

  • Remove the filter from the filter box located in the air handling unit.
  • Use a garden hose to spray the filter, ensuring to first spray the side opposite the air flow arrows, then the other side at a downward angle.
  • Wash the filter with dish soap twice a year, then repeat step 2.
  • Wait for the filter to dry.

Drying Time: Most filters take 15 – 30 minutes to dry.

ERF Group Recommendation

The first step in reducing allergen levels in your home is to ensure proper ventilation through regular, thorough cleaning and removing large particles settled on surfaces by selecting the right device. Then, if your symptoms persist, it's a good idea to look for an air purifier that can effectively eliminate particle pollution.

During our research, we found that this is a matter of personal preference. If you want to spend less money and clean the filter cells yourself, your answer will be entirely different from someone who does not want to clean the filter themselves. So, "Is an electrostatic air filter better?" is a wrong question; the correct question will be "Is an electrostatic air filter better for YOU and YOUR HOME?"

If you are not sure about making the most suitable decision for your situation, ERF Group will provide you with the safest support in this regard. ERF Group is knowledgeable about all different types of filters and will assist you in selecting the most suitable one for you.