How to solve the fan oil leakage or oil leakage into the casing How to solve the fan oil leakage or oil leakage into the casing? (1) lower the oil level; (2) change fan seal; (3) dredge the fan vent, install the plug with 2mm hole in the middle cavity, and open the cock under the wallboard. previous：Matters needing attention in installing negative pressure fan Next：How to define the manufacturing process of high strength wet curtain paper and wet curtain paper