The answer to 'when to replace sump pump' is that you should replace your sump pump every 7-10 years, or sooner if it's not working properly. Sump pumps are essential for preventing basement flooding, but they have a limited lifespan due to the wear and tear of constantly running to pump out water. Over time, the motor, impeller, and other components can wear down, reducing the pump's efficiency and reliability.
It's important to monitor your sump pump and replace it before it fails completely. Signs that it's time for a replacement include the pump running more frequently, taking longer to empty the sump pit, or making unusual noises. You should also replace the pump if it's over 10 years old, even if it's still functioning, to avoid an unexpected failure during a heavy rainstorm.