The skimmer plays an important role in your pools circulation. Water is sucked through your skimmer into your pool pump where it is then fed hrough your pump, filter, heater and back into your pool through your return jets. Having a leak free plumbing system means your pump will be quieter and last longer. Your skimmer and jets should last 20 years or longer with proper water chemistry, while most pool liners last up to 20 years. The best time to replace your skimmer and jets is when you vinyl pool liner is being replaced. This is a proactive approach in maintenance and the most cost effective as replacing it down the road when your new liner is already installed is much more costly.
Common skimmer problems on older pools:
-Shifting that causes skimmer cracks
-Sinking concrete decks that puts stress on the skimmer
-Leaky or rusty/rotten plumbing undereath the skimmer
-Weir damage (flappy thing in skimmer mouth) can sometimes break and cause your pump to draw in air
Replacing a skimmer involves cutting the concrete surrounding it, removing it from the wall and replacing the plumbing underneath the ground. Once the new skimmer is in place and plumbing attached, then the new concrete can be poured back into place.
Newer style skimmers are called wide mouth skimmers and are a rectangle shape. They skim the water better than the older style "square" mouth ones.