When comparing air purifiers, you encounter two main categories: devices with replaceable filters and so-called "filterless" devices that operate using ionization or washable electrostatic plates. Which of the two is actually better? We weigh the pros and cons.
How does an air purifier with a filter work?
A filtered air purifier draws in air with a fan and sends it through one or more filter layers, usually a pre-filter, a HEPA filter, and an activated carbon layer. Particles and gases are physically captured and trapped within the filter. Over time, the filter becomes full and needs to be replaced.
How does a filterless air purifier work?
Filterless devices usually operate using ionization or electrostatic plates. They electrically charge particles, which then either settle onto surfaces in the room (in the case of ionization) or are attracted to washable plates inside the device (in the case of electrostatic filtration). In the latter case, you do not need to buy a new filter; you clean the plates periodically.
Advantages of an air purifier with a filter
- Particles are actually removed from the air instead of settling on furniture
- A HEPA13 filter captures up to 99.97% of fine dust, pollen, bacteria, viruses, and microplastics
- No risk of ozone formation as a byproduct, unlike some ionizers
- Predictable, measurable performance (CADR) that is easy to compare between models
- Odors and gases are also addressed with an activated carbon layer
Disadvantages
- You must replace filters periodically, which entails ongoing costs
- A clogged filter reduces airflow if it is not replaced in time
Advantages of a filterless air purifier
- No recurring costs for replacement filters
- Plates are often easy to wash
Disadvantages
- With ionization, particles do not really disappear from the air; they move to surfaces, meaning you have to vacuum and dust more often
- Risk of ozone formation as a byproduct, depending on the device and the technology used
- Generally does not capture gases or odors, unlike an activated carbon filter
- The efficiency of electrostatic plates decreases as they get dirty, and regular cleaning is necessary to remain effective
- Less well-researched and standardized than HEPA filtration, making performance harder to compare
Which is better for your situation?
For people with allergies, asthma, pets, or young children, an air purifier with a genuine HEPA filter is generally the more reliable choice. The reason is simple: particles are actually removed instead of relocated, and the risk of an unintended byproduct like ozone is minimal with a device that runs entirely on filtration.
A filterless device may seem attractive because of the lower running costs, but in practice, you pay for that with less thorough air purification and more maintenance on the device itself and the surfaces in your home.
Our advice
Our advice is to choose an air purifier with a full-fledged filter system, preferably combining HEPA13 and activated carbon, rather than a filterless device that runs on ionization. The Dynter AirPure Plus PA244 uses a 4-stage filter system with a HEPA13 filter (99.97% capture efficiency for fine dust, pollen, bacteria, viruses, and microplastics) and a CADR of 260 m3/h, suitable for up to 55 m2. This way, you can be sure that pollution actually disappears from the air, rather than just ending up somewhere else in your home.