What Is the Cause of the Loud Noise in My Homes Pipes?

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If you hear a loud banging noise in your pipes, it is often referred to as water hammer. This problem can occur in normal faucets but is more common in pipes that are attached to dishwashers or washing machines. In both of these appliances, the valve is electrically operated and is known as a solenoid valve. These valves tend to close very quickly.

When the washing machine or dishwasher is filling up, the valve is open, and water is rushing through the pipe towards the appliance. Once it is full, the valve slams shut abruptly. Since there may be 5 or 10 pounds of water moving at a considerable speed in the pipe, it suddenly comes to a halt, causing the entire pipe system to shift and make the noise. If it is a long, straight pipe carrying the water, the motion and noise can be even more significant.

This issue is not great for the pipes since each time you hear the noise, it means that your pipes have been stressed and flexed. The typical solution is to use a “shock absorber” near the valve. A simple shock absorber can be a foot-long vertical pipe attached near the valve, which is filled with air. As a result, when the valve closes, the moving water rushes up into the vertical pipe and compresses the air, gradually slowing down. However, the bubble can dissolve into the water in a simple vertical pipe, so it is better to use a sealed system with a rubber bladder.

Another solution is to use a spiral of copper pipe. If this is a common occurrence throughout your plumbing system, there are different options you can try, such as installing a pressure-reducing valve on the water supply line for the house (if the water pressure is exceptionally high) or using an expansion tank on the cold water side of the water heater. Another possible solution is to ensure that ¾-inch pipes are used throughout the house since larger pipes will reduce the speed of the water.

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1. What is the loud banging noise in my home’s pipes?

The loud banging noise you hear in your home’s pipes is commonly known as water hammer. This occurs when the water flow in your pipes is abruptly stopped, causing the pipes to vibrate and create a banging noise.

2. What causes water hammer?

Water hammer is usually caused by a sudden change in water pressure. This can happen when a valve is closed too quickly, or when a high flow rate of water is suddenly stopped.

3. Is water hammer dangerous?

While water hammer is not dangerous in itself, it can cause damage to your pipes over time. The constant vibration can eventually lead to leaks or even burst pipes.

4. How can I prevent water hammer?

You can prevent water hammer by installing a water hammer arrestor. This device absorbs the shock of the water and prevents the pipes from vibrating.

5. Can I fix water hammer myself?

If the problem is minor, you may be able to fix water hammer yourself. Try installing water hammer arrestors or adjusting the water pressure in your home. However, if the problem persists, it’s best to call a professional plumber.

6. Is water hammer common?

Water hammer is a relatively common problem in homes with older plumbing systems. It can also occur in newer homes if the plumbing was not installed correctly.

7. Can water hammer damage my appliances?

Yes, water hammer can cause damage to your appliances over time. The constant vibration can cause connections to loosen and eventually lead to leaks.

8. How do I know if I have water hammer?

If you hear a loud banging noise in your pipes when you turn off a faucet or appliance, you likely have water hammer. You may also notice your pipes vibrating or shaking.

9. Can water hammer be fixed without professional help?

If the problem is minor, you may be able to fix water hammer yourself. However, it’s always best to call a professional plumber if you’re not sure how to fix it or if the problem persists.

10. Can water hammer be prevented in new homes?

Yes, water hammer can be prevented in new homes by ensuring that the plumbing is installed correctly and by using water hammer arrestors.

11. How much does it cost to fix water hammer?

The cost to fix water hammer can vary depending on the severity of the problem and the cost of labor in your area. On average, you can expect to pay between $150 and $300 for professional repairs.

12. How long does it take to fix water hammer?

The time it takes to fix water hammer can vary depending on the severity of the problem and the availability of a professional plumber. In most cases, however, it can be fixed within a few hours.

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