Corrosion is the main reason why coated fins are a preferred choice. Usually, condenser fins are present in the outdoor unit. They have to withstand several environmental factors like wind, rain, and others. Because of this, they are prone to rust which further leads to gas leakages. Compared to copper coil, aluminum coils are even more prone to rust and corrosion. To prevent such issues, coating is very important. Coating not only prevents corrosion but also helps in increase life span of an air conditioner.