How to choose an air filter?

The air filter should be configured according to the different performance requirements of different occasions, which depends on the selection of the initial effect, the high effect and the medium efficiency air filter. There are four main characteristic indicators for evaluating air filters:

1. Air filtration speed

2. Air filtration efficiency

3. Air filter resistance

4. Dust holding capacity of air filter

Therefore, when selecting the initial effect \ high effect \ medium efficiency air filter, you should also refer to these four performance parameters to make the corresponding selection.

①Select a filter with a large filter area.

The larger the filtration area, the lower the filtration rate and the smaller the filter resistance. Under certain filter structure conditions, the filter speed is reflected by the rated air volume of the filter. Under the same cross-sectional area, it is hoped that the allowable rated air volume is as large as possible, while operating under the rated air volume will increase the efficiency and reduce the resistance. At the same time, increasing the filter area is the most effective way to prolong the service life of the filter. Experience has shown that for air filters of the same structure and the same filter material. When the final resistance is determined, the filter area is increased by 50%, and the service life of the filter is prolonged by 70% to 80% [16]. However, when considering increasing the filtering area, the structure and site conditions of the filter must also be considered.

② Reasonably determine the efficiency of filters at all levels.

When designing an air conditioner, the efficiency of the last stage filter should be determined first according to the actual requirements, and then the protective pre-filter should be selected. To properly match the efficiency of air filters at all levels, make good use of and configure the optimal filtration particle size range of the coarse and medium-efficiency filters. The selection of the pre-filter should be comprehensively considered based on factors such as the use environment, spare parts costs, operating energy consumption, and maintenance costs. The minimum count filtration efficiency of air filters of different efficiency classes for different sizes of dust particles is shown in Figure 1, which usually refers to the efficiency of a new filter without static electricity. At the same time, the configuration of the comfort air-conditioning filter should be different from the purification air-conditioning system, and different requirements should be put forward for the installation and leakage prevention of the air filter.

③The resistance of the filter is mainly composed of the resistance of the filter material and the resistance of the filter structure. The dust accumulation resistance of the filter increases. When the resistance increases to a certain value, the filter is scrapped. The final resistance is directly related to the service life of the filter, the variation range of the air volume of the system, and the energy consumption of the system. Low-efficiency filters often use coarse fiber filter media with a diameter greater than 10/.,tm. The gap between fibers is large, and excessive resistance may blow away the dust on the filter and cause secondary pollution. At this time, the resistance is not high. Increase it further and the filtration efficiency is zero. Therefore, the final resistance value of the filter below G4 should be strictly limited.

④ The dust holding capacity of the filter is an index directly related to the service life. In the process of dust accumulation, the filter with low efficiency is more likely to show the characteristic that the initial efficiency increases first and then decreases. Most filters used in general comfort central air conditioning systems are disposable, and they simply cannot be cleaned or are not economically worth cleaning. Sffitech is a popular air filter manufacturer.