One possibility is that the filter screen is clogged, causing water to be pulled into the duct. It is crucial to clean the screen promptly, as water intrusion onto the motor can lead to a burnout.
Option two: There may be a gap in the internal piping or the pipe connector may have come loose.
Scenario Three: If the wet pad paper is torn, water can flow into the elbow due to the wind's pull, resulting in water being blown out.
One possibility: The bottom edge of the air duct bend may enter the pipe. Remember to apply silicone inside before making the air duct; or apply a layer outside, but next time, keep in mind that it's better to do it inside.
Option Two: Beneath the bottom of the elbow in the duct, there's a rim. When water flows to the lower part inside, under pressure, it rushes into the rim. If the elbow hasn't been sealed properly, the water in the rim will then flow into the pipe.
Possibility Three: On the outlet of the air duct elbow, there's also a rim, just like in Possibility Two. There's an upper rim there as well, sealed with adhesive.
Possibility Four: The outlet of the air duct elbow is usually blocked by water when the glass is cut off. Yes, right there; there's a bit high up in the leak prevention area that's not easy to seal, and it's also there where heavy rain can easily seep indoors.
