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Understanding Shut-Off Valve Failures

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If you've ever looked near a toilet or sink in your home, then you've probably noticed a shut-off valve. You can usually find these valves near any plumbing, and they serve an essential role. When you're having a problem with a single fixture or nearby plumbing, you can turn the shut-off valve to cut the supply of water without shutting off your home's water main.

While shut-off valves are a critical part of your home's plumbing, they often go neglected for years. Many homeowners have experienced quite a shock when they attempt to turn off the water to a leaky sink, only to discover that the valve doesn't work. Keep reading to learn why shut-off valves fail and what you can do about it.

Understanding Your Fixture Shut-Off Valves

Your home likely has several types of valves scattered throughout its plumbing. The main water valve, outside spigot shut-off valves, and individual fixture valves are likely to all be slightly different. At fixtures such as sinks and toilets, you will likely find straight or angled stop valves. These valves have small, round handles that you turn to open and close the flow of water.

Newer homes typically use ball valves, which also come in straight and angled styles. Valves of this type are easy to identify since they include a long lever and only require a quarter turn to open or close. If the lever is in line with the pipe, then the valve is open. With the lever turned across the pipe, the valve is closed.

Recognizing Valve Failures

Stop and ball valves are straightforward devices, but they still tend to fail with time and age. In most cases, the metal of the valve corrodes away, making the valve difficult or impossible to turn. This type of failure commonly occurs with older-style stop valves. When a valve seizes in this way, the handle may be completely impossible to turn by hand.

Ball and stop valves also use internal seals to help prevent water from flowing when closed. If these seals wear out or break down, water may be able to flow past the valve even when it is closed. Valves that fail this way may still marginally function, but you will find that they reduce the supply of water to a trickle when closed rather than stopping it entirely.

Maintaining and Repairing Old Valves

There's not much you can do to maintain your valves, but it's good practice to test them once or twice per year. Using your valves in this way can help to prevent them from seizing up, but more importantly, it can alert you to problems. While valve failures are not plumbing emergencies, you should consider repairing them as soon as possible so that they are available when you need them.