Cleaning/replacement and use of AHU air filters
(1) The filter should be cleaned/replaced under the following conditions:
a. Before starting up for the first time;
b. After the unit has been in operation for 3 months (the time should be appropriately shortened depending on the working environment on the unit);
c. The filter section is equipped with a resistance monitoring device, when the resistance of the filter reaches the final resistance. When the filter material of the filter is non-woven, it can be cleaned 1-2 times; for the metal mesh filter, it can be cleaned and used repeatedly.
(2) How to clean the filter: soak the filter in a moderate soap solution or detergent or water and rub it gently. Rinse with clean water and let it dry before reloading.
(3) The high-efficiency filter (including sub-high-efficiency and activated carbon filter) should be completely cleaned in the clean room and purification air-conditioning system and the system should be unpacked and installed on the spot after the system has been continuously tested for more than 12 hours. Before installation, the filter must not be deformed, fallen off, or broken. Install it immediately after being qualified, the direction must be correct, and the surrounding and interface of the high efficiency filter after installation should be tight and leak-proof.
Regularly check the dust accumulation of the filter screen of the unit. When the filter reaches its final resistance, it needs to be scrapped or replaced. The workshop staff need to record the pressure difference between the two ends of the middle efficiency every day. The pressure difference between the two ends of the middle efficiency is 1.5 times higher than the initial value. When the filter is clogged and needs to be cleaned, when the pressure difference between the two ends of the primary and secondary effect filter is lower than the initial pressure difference, check the damage of the filter. If it is damaged, it needs to be replaced in time.
According to efficiency specifications. | 建议终阻力(Pa)Resistance in the proposal |
G3(初效)Primary filter. | 100-200 |
G4(初效)Primary filter. | 150-250 |
F5-F6(中效)Middle efficiency filter. | 250-300 |
F7-F8(高中效)High and medium efficiency filters. | 300-400 |
F9-F11(亚高效)High efficiency filter. | 400-450 |
高效与甚高效 And high efficiency filter. | 400-600 |
3. The surface of the surface cooler and heater should be cleaned or blown off regularly.
4. After the surface cooler and heater have worked for 2-3 years, they should be cleaned by chemical methods to remove the scale in the pipe.
5. Regularly check the lubrication parts of the electrical equipment of the air conditioning unit and the transportation drive.
6. When the unit is shut down, if the surface cooler and heater will be below 0℃, in order to prevent the surface cooler and heater from being frozen and cracked, the internal water should be drained, and the fresh air valve should be closed or added in the pipeline Antifreeze, such as glycol solution.
Drainage procedure:
Ⅰ. Close the valves of the inlet and outlet pipes;
Ⅱ. Slowly open the air release valve on the return pipe of the unit;
Ⅲ. Slowly open the drain valve on the water inlet pipe of the unit;
Ⅳ. Drain all the remaining water. (When reinstalling, you must wrap the raw material tape and tighten).