How do I know when it’s time to replace the vinyl liner in my pool? What a great question! The answer may seem pretty obvious. We all know the main purpose of a pool liner is to keep the water contained in the pool. Once the liner no longer can perform that function, it’s time to replace it with a new one. “Well, that’s great,” you say. “But what signs should I look for that tell me the time is NOW?” Good point. There are some tell-tale signs that your vinyl liner is on its last leg and we are happy to share them with you in detail. Let’s take a look.