HVAC filters are mainly used for pre filtration of dedicated air conditioning and ventilation systems in computer rooms, purification of air conditioning clean room return air filtration, efficient pre filtration, and pre filtration of air compressors. The outer frame is made of cardboard, and the filtering material is non-woven fiber felt. The folded filtering material is used, and the back is supported by a metal square mesh. The main function is to filter impurities in the system, ensure system cleanliness, and protect the normal operation of various components. Prevent impurities from entering the system and causing wear and blockage of internal components such as heat exchangers and fans, to avoid affecting the normal operation and service life of the equipment. HVAC filters can improve thermal efficiency, and impurities that are not filtered by HVAC filters can also reduce the heat exchange efficiency of heat exchangers, greatly reducing the operational efficiency of equipment. Filtering impurities through HVAC filters can improve the heat exchange efficiency of heat exchangers, thereby enhancing the overall thermal efficiency of equipment.