How can a clogged louver bird screen collapse an intake louver?

A blocked screen can make the fan pull hard against the louver. Shut the fan down, clear/replace the screen and damaged louver, and review maintenance or pressure safety controls.

['A bird screen loaded with leaves, plastic, or debris can become the real damper in the system. A big fan can pull enough negative pressure to bend blades, collapse weak frames, or damage the intake assembly.', 'Stop the fan if the louver is deforming. Clear the obstruction only when safe, document damage, and replace any bent louver sections. For high-consequence intakes, review maintenance access, stronger screen/louver construction, and pressure monitoring/shutdown controls with the foreman/engineer.']

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