Medium-efficiency combination air filters are mainly used in intermediate filtration of air conditioning and ventilation systems, as well as in industrial purification in pharmaceuticals, hospitals, electronics, food, and other industries. They can also be used as pre-filters for high-efficiency filters to reduce the load on the high-efficiency filters and extend their service life. Due to the large air-facing surface of the combination medium-efficiency air filter, it has a large dust volume and low air velocity, and is considered to be the best medium-efficiency air filter structure currently available.

Medium-efficiency combined air filter

Mainly used in intermediate filtration of air conditioning and ventilation systems, and industrial purification in pharmaceuticals, hospitals, electronics, food, etc. It can also be used as a pre-filter for high-efficiency filters to reduce the load on the high-efficiency filters and extend their service life. Due to its large air-facing surface, the combined medium-efficiency air filter has a large dust holding capacity and low air velocity, and is considered to be the best medium-efficiency air filter structure currently available.

Medium-efficiency combined air filter

1. The main control parameters for selecting medium-efficiency air filter products include rated air volume, filtration efficiency at rated air volume, initial resistance at rated air volume, dust holding capacity, and overall dimensions.

2. According to the test methods specified in JG/T22-1999 "Performance Test Method for Air Filters for General Ventilation", a filter with an atmospheric dust counting efficiency of ≥20% and <70% for particles with a diameter ≥1.0μm is considered a medium-efficiency air filter.

3. Commonly used filter media for medium-efficiency air filters include glass fiber and non-woven fabric.

4. The manufacturer should provide the filter's dust holding capacity.

5. The initial resistance of a medium-efficiency air filter should be ≤80Pa. During design, the final resistance can be calculated as twice the initial resistance.

6. The initial resistance of the filter should not exceed 10% of the resistance in the product sample. After regeneration and cleaning with regenerable or washable filter media, the efficiency should not be less than 85% of the original specification, and the resistance should not exceed 115% of the original specification.

7. Air filters should meet fire safety requirements, and the flash point of the air filter coating should not be lower than 163℃.

8. Medium-efficiency air filters should not be used independently; they should be used in combination with coarse-efficiency air filters.

Air filters should avoid direct installation in water spray chambers or on the downwind side of humidifiers. 

If this is unavoidable, effective measures should be taken.