The water blocking plate is an important component of the central air conditioning terminal device, which is matched with the central air conditioning and functions as a steam water separation device. The water blocking plate is a key component of the modular air conditioning unit, which can be used in both high and low wind speeds. Fiberglass or PVC materials can be used, which have the characteristics of low resistance, light weight, high strength, corrosion resistance, aging resistance, good water vapor separation effect, easy cleaning, and durability. The PVC water baffle, which is mainly made of PVC resin, maintains the proper rigidity, impact resistance, aging resistance, corrosion resistance and fire protection of the water baffle. Continuous extrusion molding successfully maintains the density and precise geometric dimensions of the water blocking plate, allowing for arbitrary determination of the length of the water blocking plate. PVC waterproof board can work continuously and normally in an environment of 90 ℃ -25 ℃.