Can the HEPA filter in the air purifier be washed?
Replacing the filter element is a direct method, but some friends worry that the cost of replacing the filter element is too high. Indeed, the price of HEPA filters for air purifiers ranges from 200-1000 yuan. Taking the air conditions in Beijing as an example, if it is turned on for 8 hours a day, the filter must be replaced once in the first half of the year. Have to spend 400-2000 yuan.
The filters of the air purifier include a pre-filter, an activated carbon filter and a HEPA filter. Of course, more and more manufacturers now choose a composite HEPA filter that sandwiches activated carbon particles in the HEPA filter to enhance the filtering effect of the filter.
Among them, the pre-filter is used to filter pollutants such as large particles and dust hair in the air, which can be directly washed with water or sucked up with a vacuum cleaner. The activated carbon filter is mainly used to absorb odors and formaldehyde in the air. It can also be used repeatedly as long as it is regularly exposed to the sun.
Only the HEPA filter can neither be washed nor cleaned by exposure to the sun, and cannot be reused. Why can't the HEPA filter be washed directly?
First of all, let's take a look at the material of the HEPA filter.
There are many kinds of materials that make up the HEPA filter, which can be divided into PP (polypropylene) high-efficiency filter paper, PET filter paper, PP and PET composite high-efficiency filter paper and glass fiber high-efficiency filter paper. Among them, PP (polypropylene) is paper, so it is generally not washable.
The other part of the HEPA filter is made of PET or PTFE, which is the origin of many claims on the Internet that the HEPA filter is washed with water. However, the efficiency of this type of HEPA filter is very low and is not recommended.
PET material HEPA filter
In addition, the purification principle of the HEPA filter is not as simple as filtering out particles larger than the mesh like a sieve to purify Air. The HEPA filter relies on the van der Waals force between the fine particles and the filter to form an adsorption effect. When brushing with water, the electrostatic adsorption capacity of the filter is also destroyed. electric fan.
So, the HEPA filter can't be washed with water. If you feel that the HEPA filter at home has become dirty after using it for a long time, then just replace it with a new one, don't worry about money.