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Reliance Plumbing Sewer & Drainage, Inc. Blog

“Why Are My Pipes Knocking?”

Shocked and surprisedSo you hear a strange noise coming from behind your walls—you might even think it’s coming from the front door, but you check, and it’s not—it’s a knocking sound of some kind.

Don’t worry, your house is probably not haunted, but we don’t judge you if that’s the conclusion you jumped to. What you’re actually hearing is sometimes called water hammer. This is a fairly common occurrence. However, it does indicate a problem—one that can only be remedied by a professional plumber in Skokie, IL. Keep reading to learn more about this issue.  

What Causes Water Hammer?

This is what happens when the water flowing through your plumbing pipes is brought to a sudden stop or is forced to change direction abruptly, like when a tap is turned off. What this does is generate a sudden surge in pressure, and the vibrations in the pipe create the knocking sound you hear.

But, why doesn’t this happen all the time, then? Shouldn’t you hear it anytime you turn off a faucet, or when an appliance stops demanding water? Well—no… because your plumbing system is equipped with air chambers that are designed specifically to prevent these pressure spikes. If you begin encountering water hammer on a regular basis, it typically means that the air chambers are waterlogged.

Why Is This Bad for Your Plumbing?

The issue with water hammer isn’t the noise it makes (although the noise can certainly be disruptive and annoying). It’s the increase in water pressure. Pressure spikes can start to cause damage in your pipes. It could even potentially cause burst pipes. Additionally, too much pressure can negatively impact your appliances, such as the dishwasher and clothes washer.

When water hammer continues within your plumbing system consistently, it will eventually lead to inconvenient and costly problems. So be sure to call in a professional plumber right away when you notice this sound.

Stopping Water Hammer

How our professional plumbers stop your water hammer will depend on what the exact cause is. For instance, as we mentioned above, the most common cause is that the air chambers are water logged, and we may need to restore the air in them. These chambers are vertical pipes near the valves on the main pipes. A plumber can drain out all the water from the plumbing system and fill up the air chambers again. Additionally, the chambers might need to be cleaned.

Another potential cause of water hammer is that the water pressure in your plumbing is too high. This is quite often a municipal issue, so what your plumber will do in this case is install a pressure-reducing valve (water pressure regulator). The regulator will lower the pressure in the plumbing between 30-55psi. You really only want to trust this job to a pro, so that you know the pressure is correct and not at a dangerous level, for your plumbing system as well as your safety.

For expert plumbing service, installations, or maintenance contact Reliance Plumbing Sewer & Drainage, Inc. Our knowledgeable plumbers serve the North Shore and Northwest Chicago suburbs. Rely on Reliance!

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