It might be self-explanatory, but if the window won’t open or is giving you trouble, it’s time to replace it. It’s frustrating, especially since using Windows should be quick and easy. You need your windows for ventilation, so it’s important to know when it’s time to replace them. This problem gets worse over time as the hinges sometimes rust from disuse and other problems arise. If this happens to you, it’s probably a sign that it’s time to replace the window.