What are the key installation precautions for cartridges? What happens if installed backwards?

Key installation points: 1) Distinguish inner and outer sides — the pleated outer side is the air-inlet face and the inner side the outlet; installing backwards is strictly prohibited; 2) Ensure the top seal ring is tight and aligned with no looseness or offset to prevent air leakage; 3) Tighten bolts evenly to avoid cartridge deformation and gasket misalignment; 4) Clean debris from the housing before installation to avoid scratching the media. If a cartridge is installed backwards, dust enters its interior and cannot be removed by pulse cleaning, quickly clogging the cartridge and causing loss of suction and excessive emissions.