Which is better ? HEPA or Electrostatic ioniser filter ? Part 2
There are several Electrostatic or Ioniser (Ionisator in Dutch) air purifiers in market. The main argument of this type of air purifier is “No need to replace filter”. Well, there are some disadvantages due to its mechanism. Base on the same energy consumption, the filtration efficiency of Electrostatic filter is quite low than HEPA filter.
- Many experiments have showed that the filtration efficiency of Electrostatic filter decreases while air flow increases. If it wants to increase the capacity, it must increase voltage, which cost more energy and produce more unwilling (ongevraagd?) ozone. It could even cost 50% more energy than HEPA filter with same CADR (Clean Air Delivery Rate).
- Because the mechanism of Electrostatic filter is not based on Brownian motion and Van der Waals force, the capability of filtration will decrease with even smaller particles. Therefore, that, many of Electrostatic filters claim the same efficiency and capability as HEPA filter, is highly open to doubt.
Will the HEPA filtration efficiency decreases with time?
Actually, is increasing. After being used for a period, the porosity of filter should become smaller because of accumulated particles inside filter. But, when the porosity become smaller, it will cause the loading of motor because the air flow rate becomes lower. Therefore, we must change the filter regularly or choose smart filter, for instance, HEPASmart from BRISE air purifier.
Can a filter be used for 10 years?
No. Please do not do that. There are many dust, mould, bacteria and dirty particles attached on filter, can you image that how many bacterias will multiply…etc after some period? Even you wash it or vacuum it. With so many micro particles on it, better throw it away and replace with a new filter to make sure there would be no secondary pollution coming from filter.
Do I change the filter when the indication light is on?
The conventional air purifiers are lack of sensor mechanism so they do not know the status of filters. Often they use Timer to remind you. But, this is very inaccurate because everyone’s situation is very different. So, Timer is not able to tell the real status of filter. If you have this kind of air purifiers at home, do not really trust the indicator. You should regularly check the filter every 2 months. If you discover the filter is very dirty, replace it ASAP.
Thanks to new IoT technology, now you can also choose the intelligent air purifier like BRISE C200. It uses sensors and data science to calculate the life time of filters accurately. This HEPASmart technology ensure the best balance of your heath and cost on filter.