Primary, middle and high efficiency filter maintenance and maintenance

1. All kinds of air filters and high efficiency air filters are not allowed to tear or open the packaging bags or packaging films by hand before installation; The air filter should be stored in strict accordance with the direction standard marked on the HEPA filter packing box; In the handling process of the HEPA filter, it should be handled and put gently to avoid violent vibration and collision.

2. For the HEPA filter, the installation direction must be correct: when the corrugated plate combination filter is installed vertically, the corrugated plate must be perpendicular to the ground; Filter in the connection between the vertical and the frame, no leakage, deformation, damage and glue leakage, etc., after installation must ensure that the inner wall clean, no dust, oil, rust and debris, etc.

3. Inspection method: observation or white silk cloth wipe inspection.

4. Before the installation of the HEPA filter, the clean room must be comprehensively cleaned and wiped. If there is dust in the air conditioning system, it should be cleaned and wiped again to meet the cleaning requirements. If HEPA filters are installed in the technical interlayer or ceiling, the technical layer or ceiling should also be thoroughly cleaned and wiped.

5. Transportation and storage of HEPA filters should be shelved in accordance with the direction of the manufacturer's logo. In the process of transportation, should be handled with care, to prevent violent vibration and collision, can not be forced loading and unloading.

6. Before installing the HEPA filter, you must unpack the HEPA filter on the installation site for appearance inspection, including: whether the filter paper, sealant and frame are damaged; Whether the side length, diagonal line and thickness size meet the requirements; Frame without burr and rust (metal frame); Whether there is product qualification certificate, whether the technical performance meets the design requirements. Then according to the national standard "clean Room Construction and acceptance Code" [JGJ71-90] for the method of inspection, qualified should be installed immediately.

7. For HEPA filters with cleanliness level equal to or higher than 100 for clean rooms, leakage detection should be carried out according to the method specified in the Clean Room Construction and Acceptance Code [JGJ71-90] before installation, and meet the specified requirements.

8. When installing the HEPA filter, the arrow on the outer frame should be consistent with the airflow direction; When it is installed vertically, the filter paper crease direction should be perpendicular to the ground.

9. Install rough effect flat or folding filter, should make the galvanized mesh surface in the back direction of the air outlet. When installing the bag filter, the length direction of the filter bag should be perpendicular to the ground, and the direction of the filter bag should not be parallel to the ground.

10. Under normal conditions of use, flat, foldable coarse or medium effect filter, generally 1 to 3 months to replace once, the requirements of the area is not strict, the filter material can be replaced down can be soaked with water containing detergent, rinsing, and then cool dry and then change; Generally, after washing 1-2 times, a new filter must be replaced to ensure filtration efficiency.

11. For bag type coarse effect or medium effect filter, under normal use conditions (average 8 hours a day, continuous operation), generally used for 7-9 weeks should be replaced.

12. For sub-high efficiency filter, under normal conditions of use (average 8 hours a day, continuous operation), generally used for 5- 6 months, should also be replaced.

13. For the above filters, if there is a differential pressure gauge or differential pressure sensor before and after the filter, the coarse effect filter must be replaced when the differential pressure value is greater than 250Pa; For medium effect filter, when the pressure difference is greater than 330Pa, it must be replaced; For the sub-high efficiency filter, when the pressure difference is greater than 400Pa, it must be replaced, and the original filter can not be reused;

14 for the high efficiency filter, when the filter resistance value is greater than 450Pa; Or when the air velocity on the outlet surface drops to a low limit, even after the replacement of coarse and medium effect filters, the air velocity still cannot be increased; Or when the surface of the HEPA filter can not be repaired leakage, must be replaced with a new HEPA filter; If the above conditions are not available, it can be replaced once every 1-2 years according to the use of environmental conditions.

15 in order to give full play to the role of the filter, in the selection and use of the process, the filter face wind speed, coarse effect, medium effect filter should not be greater than 2.5m/s, sub-high efficiency filter and high efficiency filter should not be greater than 1.5m/s, which is not only conducive to ensure the efficiency of the filter, can also extend the service life of the filter, cost saving.

16. Generally do not replace the filter when the equipment is in operation; If the filter cannot be stopped for replacement because it has reached the replacement deadline, it is only allowed to replace the coarse and medium effect filter in the case of no stop fan; The sub-HEPA filter and HEPA filter can be replaced only after the air supply is stopped.

17. The gasket between the filter and the connecting frame must be tight and leak-free to ensure the filtration effect.

18. For HEPA filters that need to be used in high humidity and temperature environment, filter paper, separator and frame materials that are resistant to high temperature and humidity must be selected to meet the production requirements.

19 biological clean room and medical clean room, must choose the filter of metal frame body, and its surface should not be easy to rust, do not allow the use of wood frame plate filter, in order to prevent bacteria, affect the quality of products.