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Water hammer is a common issue in many homes, creating loud banging noises in the pipes when you turn off a tap or valve. Not only is this noise disturbing, but it can also indicate more serious plumbing issues if not addressed. In this article, we’ll discuss what water hammer is, its causes, how to fix it, and prevention tips to keep your plumbing system working smoothly.
Key Takeaways
- Water hammer is caused by changes in water flow within the pipes, which creates a shockwave and results in a banging or hammering sound.
- High water pressure, fast-closing valves, and loose pipes are some of the most common causes of water hammer.
- Fixing water hammer may involve installing water hammer arrestors, adjusting water pressure, and securing pipes.
- Prevention is key, and regular maintenance can help avoid future issues with water hammer in your plumbing system.
Now, let’s break down everything you need to know about water hammer and how to address it effectively.
What is Water Hammer?
Water hammer, also known as hydraulic shock, occurs when water flowing through the pipes suddenly comes to a stop or changes direction. The abrupt change in the flow of water causes a shockwave, which creates a loud banging noise in the pipes. This sound is caused by the pressure of water pushing against the walls of the pipes, which can result in physical damage to the plumbing system if left unchecked.
Water hammer can happen at any time, but it is most commonly heard when you turn off a tap or close a valve quickly, causing the water to abruptly stop. This shockwave can cause damage to pipes, joints, and even appliances connected to the plumbing system.
Causes of Water Hammer
Several factors can contribute to water hammer. Understanding these causes can help you pinpoint the problem and apply the right solution.
High Water Pressure
One of the leading causes of water hammer is high water pressure. When the water pressure is too high, it creates more force in the pipes, making the system more prone to shockwaves when the flow of water is suddenly stopped. This can result in banging noises that are not only annoying but can also strain the plumbing system and lead to leaks or burst pipes.
Fast-Closing Valves
Fast-closing valves, such as those found in dishwashers, washing machines, and toilets, can create water hammer. When these valves close quickly, the water flow stops abruptly, causing a shockwave to travel through the pipes. This sudden change in pressure is a common cause of water hammer.
Air Chambers
Air chambers are small, vertical pipes located near appliances or fixtures. They are designed to absorb the shockwave created when water flow is suddenly stopped. Over time, however, these air chambers can become filled with water and lose their effectiveness. Without an air chamber, there is nothing to absorb the shockwave, and water hammer occurs.
Loose Pipes
Loose pipes can exacerbate the effects of water hammer. When pipes are not securely fastened to the wall or other surfaces, they are free to move when the water flow stops suddenly. The movement of the pipes amplifies the banging noises associated with water hammer and can cause damage to the plumbing system over time.
Rapid Flow Changes
Changes in water flow, such as the sudden opening or closing of faucets, can create a surge of water pressure in the pipes. This rapid change in flow causes a shockwave that travels through the pipes, leading to water hammer. The quicker the change in flow, the more intense the shockwave will be.
Solutions to Fix Water Hammer
Fixing water hammer can often be done through relatively simple adjustments to your plumbing system. Here are some of the most effective solutions to eliminate this issue.
Install Water Hammer Arrestors
Water hammer arrestors are devices designed to absorb the shockwave that causes water hammer. These arrestors contain a chamber filled with air or gas that compresses when water flow is suddenly stopped, preventing the shockwave from travelling through the pipes. Installing water hammer arrestors at key points in your plumbing system, such as near faucets, dishwashers, and washing machines, can significantly reduce the banging noises associated with water hammer.
Adjust Water Pressure
If your home’s water pressure is too high, it could be causing water hammer. You can check the water pressure with a pressure gauge, and if it exceeds 80 psi, it may be time to adjust it. Lowering the water pressure can prevent shockwaves and reduce the chances of water hammer occurring. Many homes are equipped with a pressure regulator, but if yours is not, it’s a good idea to have one installed by a professional plumber.
Secure Loose Pipes
Loose pipes are a common cause of water hammer, as they amplify the shockwave when the water flow stops. If your pipes are not properly secured, they can bang against the walls or other surfaces, creating loud noises. To fix this, inspect the plumbing and use pipe brackets or clips to secure loose pipes. This will minimise movement and reduce the noise caused by water hammer.
Replace Fast-Closing Valves
If water hammer is being caused by fast-closing valves, replacing them with slower-closing valves can help prevent the problem. Slower-closing valves allow water to gradually stop flowing, reducing the shockwave and preventing water hammer. These types of valves are often used in commercial settings but can also be installed in residential plumbing systems.
Drain Air Chambers
If your air chambers are filled with water, they will no longer be able to absorb the shockwave, leading to water hammer. To fix this, you can drain the air chambers and restore their function. To do this, turn off the water supply and open all the faucets in the house. Once all the water has drained, close the faucets and turn the water supply back on. This should restore the air chambers’ ability to absorb shockwaves.
Pro Tips!
Here are some additional tips to help prevent water hammer and keep your plumbing system in top condition:
- Regular Maintenance: Regular inspections of your plumbing system can help identify potential issues before they become serious. Check for loose pipes, worn valves, or blocked air chambers during routine plumbing inspections.
- Water Pressure Check: It’s a good idea to check your home’s water pressure periodically to ensure it’s within the recommended range (40-80 psi). High pressure can lead to water hammer, while low pressure can cause other plumbing issues.
- Upgrade Old Plumbing: If your plumbing system is old, you may want to consider upgrading to modern pipes and fixtures. Older plumbing systems are more prone to water hammer, and new, high-quality materials can help prevent this issue.
- Install Soft-Close Valves: For new installations, opt for soft-close valves, which are designed to reduce water hammer by slowing down the closing process.
Conclusion
Water hammer may seem like a minor issue, but if left unchecked, it can lead to serious plumbing problems. Fortunately, with the right solutions—such as installing water hammer arrestors, securing loose pipes, and adjusting water pressure—you can eliminate the banging noises and prevent further damage to your plumbing system. Regular maintenance and attention to your plumbing system are key to avoiding water hammer and keeping everything running smoothly.
Contact Rae.Co Plumbing for Plumbing Services
If you’re dealing with water hammer or any other plumbing issues, Rae.Co Plumbing is here to help. With over 10 years of experience, our licensed and insured team is ready to provide the expert plumbing services you need. We offer upfront pricing, fast local response, and 24/7 emergency services. Contact us today for reliable plumbing solutions!