Choose the filters with large filtration area

The area of the filter material in a filter is called the " filtration area ".

With the exception of a small number of low efficiency filters, the filtration area of a filter is often several, dozens, and sometimes up to a hundred times that of the windward side of the filter.

Most of the captured dust is concentrated on the windward side of the filter material. With a large filtration area of the filter, more dust can be held and the filter's service life will be longer.

With a large filtration area, the velocity of the airflow through the material is low, and the resistance of the filter is low. (Figure 4-1)

Increasing the filtration area is the most effective means of extending the life of the filter.

Experience shows that, for the same structure, the same media filter, when the final resistance is determined, the filtration area increases by 50%, the service life of the filter will be extended by 70% to 80%; doubled, the service life of the filter will be about three times of the original.

With more filter media, the price of the filter will increase accordingly, but the extension of the filter life will certainly be higher than the increase in the price of the filter. In addition, after the filtration area increases, the initial resistance will be reduced, and the energy cost of the air-conditioning system will be more or less reduced.

Certainly, when increasing the filtration area, the structure of the filter and the site conditions should be taken into account. For example, bag filters, the filtration area can be increased by increasing the number of filter bags and the length of filter bags. For traditional deep pleated filters, the spacing of the separators can be reduced to increase the number of filter paper according to the actual situation. In newly designed projects, the filter that can hold more filter material should be selected.

The size of the filtration area does not have much effect on the efficiency of the filter. Some shrewd contractors use small, inexpensive filters temporarily during the installation and commissioning stages of the air-conditioning system, the filters of the original design are then replaced when the project is handed over.

Point: For the end user, it is definitely cost-effective to choose a filter with a large filtration area.