Blog: How Air Purifiers Work: The Unfiltered Truth
Updated: Nov 17, 2020
(Written for Welter Heating)
You may have heard that the quality of indoor air is often more polluted than outdoor air. So, why not just open a window? While letting in fresh air is an excellent way to improve air flow, it doesn’t exactly eliminate all allergens, bacteria, and smells lingering in the air. Besides, have you met a Minnesota winter?
Instead of open windows, the EPA recognizes air purifiers as a primary way to improve indoor air quality. If you’re looking for the unfiltered truth, read on to learn about the different types of air purifiers, how air purifiers work, and some of the key benefits that air purifiers offer.
How 7 Popular Air Purifiers Work
All air purifiers are not the same. Among the seven most popular types of air purification systems, there are fundamental differences in how they clear the air. Some purifiers trap it, others zap it, and one system just lets it all out.
Central Air Cleaner
Central air cleaners work by passing air through a filter attached to the household cooling or heating system. The filter is placed in a housing between the furnace and the return duct, removing air pollutants and protecting the furnace from damage due to rust or dust build-up.
The system’s usefulness is linked, in part, to the type of filter that is used. While fiberglass filters have long been the standard for these systems, there are newer options that block more pollutants from passing through to the air supply. For example, a filter with a pleated design offers more surface area to catch particles, and a tighter weave means that there are smaller gaps for the particles to push through.
Central air cleaners can remove up to 99% of pollen particles, 98% of the dust, and 94% of the viruses in your home. However, because the filters block airflow, they can decrease heating and cooling efficiency.
HEPA (High-Efficiency Particulate Air) Air Purifier
HEPA air filters take air quality, and the density of the material, up a notch. These air filters remove virtually all—99.97%—of airborne allergens and dust particles that are 0.3 microns or larger.
However, HEPA air filters still have limitations. For one thing, these filters are incompatible with most whole-home systems because, in catching such small particles, they significantly slow down the airflow. The other drawback? Despite the high density of the filters, microorganisms smaller than 0.2 microns, such as germs, viruses, and bacteria, can still sneak through.
Electronic Air Cleaners
This whole-home solution works with your furnace or air conditioner to charge and trap airborne particles using static electricity. Electronic air cleaners are specifically designed to use HEPA filters as a first level of protection. Any remaining particles are trapped by electrically charged filters. Electronic air cleaners can remove up to 99.98% of airborne allergens.
Ultraviolet Air Purifiers
In some air purifiers, an ultraviolet (UV) light bulb is used to neutralize 99.9% of potentially harmful viruses, bacteria, pathogens, and mold spores that pass through the system. The UV light destroys microorganisms by breaking molecular bonds in their DNA. In many cases, the UV light is an add-on to a HEPA air purification system, allowing people to get protection from both allergens and bacteria.
Activated Carbon Air Purifiers
Activated carbon is often incorporated into air purification systems because it is incredibly porous and excels at catching the particles responsible for bad odors. Some particles get stuck as they try to pass through the carbon filter, and electrostatic attraction of the activated carbon draws in additional substances.
Activated carbon air purifiers are the only type of air purifiers specifically designed to eliminate odors, chemicals, fumes, smoke, and gasses from the air. There is a downside, however; unless the model includes a HEPA air filter, they are less effective at removing pollen, dander, dust, or mold from the air.
Out with the stale air, in with the outside air. Air exchangers are simple in concept and practice. They use one fan and vent system to blow indoor air outside, while another pulls in the fresh air.
Ionic Air Purifiers
Ionic air purifiers work by changing the electrical charge of the neutrally-charged molecules in the air. Using a method called “corona discharge,” the system emits a powerful electrical field. As electrons pass through this field, they change and become either positively or negatively charged.
Charged particles are attracted to particles with the opposite charge. When the positive and negative electrons combine, they settle out of the air. These systems are effective against allergens, bacteria, and household odors.
Four Key Benefits of Air Purifiers
While everyone can benefit from an air purifier, some factors may drive someone to select one type over another. Here are top benefits along with the systems that deliver the best results.
Air purifiers trap airborne allergens
Pollen seasons are shifting and increasing in length—not great news if you’re one of the 50 million people that suffer from seasonal allergies. However, the good news is that virtually all air purifiers provide some level of help. If you live in high allergen areas or have severe seasonal allergies, there are air purification choices that can ratchet up your comfort level. If removing allergens is a priority, consider:
HEPA air purifier
Electronic air cleaner
Ionic air purifier
Air purifiers stop germs from spreading
It almost seems crazy that an air purifier can keep you healthier during the cold and flu season, but it’s true. While a central air cleaner can eliminate up to 94% of the viruses from your home, there’s still room for improvement. Your best bets for germ control:
UV germicidal light
Ionic air purifier
Air purifiers neutralize cooking odors and smoke
While you may enjoy a fish fry, it’s unlikely that you want to suffer the greasy fishy smell in your curtains for months to come. Fortunately, some air purifiers can help remove unpleasant odors from food, chemicals, and cigarettes before they nestle into your upholstery.
If controlling odors and smells is your top priority, consider the following:
Carbon activated air filter
Ionic air purifier
Air purifiers remove asthma triggers
Poor air quality can precipitate asthma attacks. Triggers can include dry skin cells, dirt, dust, carbon monoxide, household cleaners, paint products, fragrances, and mold spores—most of which can be mitigated with an air purification system. Since triggers can be both airborne allergens and offending smells, ideal choices would be:
HEPA air filter which leverages activated carbon
Ionic air purifier
Our Top Choice: The iWave-R Ionizing System
Ionic air purifiers deliver all the top benefits of air purifiers. They reduce allergens, germs, and odors. And now there’s another reason to consider an ionizing system: With iWave self-cleaning air purification system there is no maintenance required. Unlike other air purification systems, there are no filters or bulbs to be replaced. After it’s professionally installed, it practically runs itself.
Let’s Clear The Air
Are you interested in learning more about the iWave system or other air purifiers? Contact us for more information and advice about our air purification services and which air purifier is best for your home and HVAC system.