It's cold. After heating, the air quality becomes worse. Air purifier is the key to haze removal. The filter type purifier has mature technology and high market share. It is generally composed of fan, prefilter and multiple filters with different functions. One of the main role is the filter screen, but the filter screen will absorb a lot of dust in the process of use, which needs to be cleaned and maintained regularly, otherwise the purification effect of the air purifier will become worse, and even the noise will become larger. I'll ask you if you're afraid! If you don't change the filter screen, you will buy the air purifier for nothing. Let's have a look.
First, it is necessary to see whether the screen needs to be replaced
1. Judge according to the service life of the filter screen indicated by the product;
2. The air volume of the air outlet decreases obviously and the noise increases;
3. PM2.5 measured at the air outlet is obviously higher;
4. The air outlet has obvious odor;
5. Change the color. Replace the screen (especially HEPA) as soon as possible after the color is blackened.
Before cleaning the filter screen, in order to ensure safety, before cleaning, first disconnect the power supply, refer to the manual, open the door of the air purifier filter element, and take out the filter screen in turn. If you do not know the filter element type of the home purifier, you can refer to the manual, or open the filter cover to check the identification information on the filter screen, and start to clean it.
Pre filter screen
The pre filter screen (also known as the front screen / primary filter screen) is the first layer of the air purifier screen and the most dirty one.
Cleaning cycle: according to the frequency of use, it is usually appropriate to clean 1-2 times a month.
Cleaning steps are: Wipe / suck, wash and dry.
Specific operation: use cloth / vacuum cleaner to remove dust. If you feel that the cleaning is not thorough enough, you can also wash with water, remember to use a soft brush.
Activated carbon filter screen
The main function of the activated carbon filter screen is to remove formaldehyde, toluene, etc. and odor and deodorization of VOCs.
Cleaning cycle: it is recommended to clean and dry at least once a month for newly decorated users, rainy season in South China and rainy season in North China; in other cases, the cleaning cycle can be adjusted according to different use frequency.
Cleaning steps are: Wipe / suck, and dry.
Specific operation: the dust on the surface of the activated carbon filter screen can be wiped with dry rag or cleaned with vacuum cleaner at low level. Due to the particularity of pore structure and solid property of activated carbon, it is not recommended to wash water without clear explanation.
The clean filter screen is placed in the outdoor sunlight, and the front and back sides are exposed for 2-3 hours respectively, so that the heating "desorption" can be achieved, and the effect of "regeneration" of activated carbon can be achieved. Although the effect is limited and the fate of the final replacement cannot be rewritten after 3-4 times of exposure, it is necessary to keep the purification effect of the filter screen and reduce the risk of secondary pollution.
HEPA screen
HEPA high efficiency air filter has the characteristics of high wind resistance, large dust capacity and high filtration precision.
Cleaning cycle: according to the use frequency and pollution status, it is usually cleaned once in 1-2 months, and the time of cleaning can be judged according to the accumulated use time.
The cleaning steps are as follows: suction / wiping and sun drying.
Specific operation: as the material of HEPA filter screen belongs to paper, if there is no specific mark, it can not be washed and cleaned, otherwise the pore structure of filter screen will be changed and even block, which will directly affect the purification effect.
Dust on the screen surface (except HEPA) can be cleaned by vacuum cleaner or wiped with dry cloth and paper towel, and properly dried. If conditions are available, ultraviolet sterilization can be carried out; however, if it is found that the original white screen color is blackened, it must be replaced as soon as possible. Pay attention not to scratch the screen surface during cleaning.
After all cleaning, the installation is finished. It should be noted that the removed parts and filter screen should be installed in the order from inside to outside (pay attention not to install it in reverse). After confirming that there is no error, power on for startup test, and some brands need to reset the filter element if the filter element is replaced.
Q & A on various filter screens:
It is good to replace the filter screen of each layer directly by time. Is it necessary to clean it?
The pre filter screen is silk mesh and can be reused. It mainly intercepts dust, hair, dander and other large particles of debris and pollutants. If it is not cleaned in time, the air inlet will be affected and the Cadr (air purification capacity) will be affected.
As the name implies, the activated carbon filter screen contains a large amount of activated carbon, and also contains carbon cloth (the service life is relatively short). The adsorption of activated carbon to substances can be said to be non selective. Except that some macromolecules cannot enter the pore size of activated carbon, pollutants, odors and water in the air will be absorbed. This is also the reason why the filter screen will become damp or even have peculiar smell after using for a period of time When the indoor air humidity is high.
HEPA filter screen has limited dust capacity. After a period of use, the filtration adsorption capacity will also decrease. If it is not cleaned and replaced in time, the wind resistance will be increased, the noise will be increased, and the purification effect will be affected.
Is the higher the efficiency of HEPA filter screen is?
HEPA filter screen is the most important way to remove particulate pollutants (PM2.5, etc.) and has certain filtering effect on bacteria. It can be said that it is the core component of filter screen. At present, many air purifiers will choose H13 filter screen.
H13 is in accordance with the European Union standard, the filtration efficiency of particles with particle size above 0.3 μ m is higher than 99.97%. This kind of filter screen will be very expensive, while the filter screen of 1-2 grades lower than it can theoretically be more than 99% and more than 95%;
The higher the filtration efficiency of HEPA filter screen is, the greater the wind resistance will be under the same wind force, the corresponding energy consumption and noise will be increased, and the air tightness requirements of the air duct will also be high;
At the same time, high air resistance will directly lead to small air output (Cadr will become smaller), which will reduce the purification capacity. Therefore, we should comprehensively consider that the filtration efficiency of the filter screen should not be blindly higher, but should pay attention to the cleaning and replacement in the later stage.
