Direct answer
A protective vent provides a controlled gas and vapor path that reduces pressure differences and supports moisture-vapor diffusion, helping lower—but not eliminate—the conditions that cause condensation.
Why condensation occurs
Temperature changes alter the pressure and relative humidity inside a sealed enclosure. If an internal surface drops below the local dew point, water vapor can condense. A vent helps the enclosure breathe more gradually and can reduce seal pumping that draws moisture through imperfect interfaces.
Important limitation
A vent is one part of moisture management. Enclosure drainage, desiccants, material outgassing, thermal design, vent position and exposure conditions may also matter. Validate the complete enclosure through temperature cycling and water-exposure testing.