What indicates that a window's hermetic seal may be compromised?

The presence of streaks or condensation on the panes is a key indicator that a window's hermetic seal may be compromised. A hermetic seal is designed to be airtight, preventing moisture from entering the space between the panes of glass. When this seal fails, humidity from the outside can infiltrate the space, leading to condensation forming on the interior surfaces of the glass. This buildup of moisture can result in streaks as the condensation settles unevenly or evaporates. Over time, this moisture can also contribute to mold growth and reduce the insulating properties of the window.

Visible cracks in the glass, while they can certainly compromise the integrity of the window, do not specifically indicate a failure of the hermetic seal, as they may not affect the area between the panes. Drafts near the window are more indicative of issues with the window's frame or installation rather than the hermetic seal itself. Non-functioning window locks relate to the security and operability of the window, with no direct correlation to the integrity of the hermetic seal. Therefore, observing streaks or condensation is the most direct sign that the hermetic integrity of the window has been compromised.