Water Hammer Arrestors for PEX Pipes: The Ultimate Guide to Protection and Peace of Mind

Water hammer is a common plumbing problem that occurs when water flow is suddenly stopped, creating a pressure surge that can damage pipes and appliances. While water hammer arresters are often recommended for metal pipes, the question arises: does PEX pipe need a water hammer arrestor?

Understanding Water Hammer

Water hammer is caused by the momentum of moving water. When a valve is closed abruptly, the water flowing through the pipe is forced to stop suddenly. This creates a pressure surge that travels through the pipes at the speed of sound.

PEX Pipe Properties

PEX (cross-linked polyethylene) pipe is a flexible, durable plastic piping material. It is commonly used in plumbing systems due to its resistance to corrosion, freezing, and scaling. Unlike metal pipes, PEX pipe is more elastic and can absorb some of the pressure surge caused by water hammer.

Does PEX Pipe Need a Water Hammer Arrester?

The answer to this question is not always straightforward. While PEX pipe is less susceptible to water hammer damage than metal pipes, it can still benefit from the use of water hammer arresters in certain situations:

• Long Runs of Pipe: In long runs of pipe, the pressure surge created by water hammer can travel a greater distance and cause more damage. Water hammer arresters can help to absorb the surge and prevent damage to pipes and appliances.
• High-Pressure Systems: In systems with high water pressure, the pressure surge caused by water hammer can be more severe. Water hammer arresters can help to reduce the pressure surge and protect pipes and appliances.
• Sudden Valve Closures: If valves are closed abruptly, the pressure surge created by water hammer can be more intense. Water hammer arresters can help to slow down the valve closure and reduce the pressure surge.

Types of Water Hammer Arresters

There are two main types of water hammer arresters:

• Air Chamber Arresters: These arresters use a chamber filled with air to absorb the pressure surge.
• Mechanical Arresters: These arresters use a piston or spring to absorb the pressure surge.

Installation and Maintenance

Water hammer arresters should be installed at the ends of long runs of pipe, near valves, and near appliances that are sensitive to water hammer. They should be sized appropriately for the pipe diameter and water pressure.

Regular maintenance of water hammer arresters is essential to ensure their proper function. Air chamber arresters should be checked periodically for leaks and the air pressure should be adjusted as needed. Mechanical arresters should be inspected for any signs of damage or wear.

Additional Measures to Prevent Water Hammer

In addition to water hammer arresters, there are other measures that can be taken to prevent water hammer:

• Slow Valve Closures: Avoid closing valves abruptly. Close valves slowly and smoothly to minimize the pressure surge.
• Insulate Pipes: Insulating pipes can help to reduce heat loss and prevent the expansion and contraction of pipes, which can contribute to water hammer.
• Use Flexible Connections: Flexible connections, such as braided stainless steel hoses, can help to absorb some of the pressure surge caused by water hammer.

Recommendations: Mitigating Water Hammer for Optimal Plumbing Performance

While PEX pipe is less susceptible to water hammer damage than metal pipes, it can still benefit from the use of water hammer arresters in certain situations. By understanding the causes and effects of water hammer, implementing preventative measures, and installing and maintaining water hammer arresters, you can effectively mitigate this common plumbing problem and ensure the longevity and performance of your plumbing system.

Frequently Asked Questions

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

• Listen for banging or knocking noises in pipes when valves are closed or water fixtures are turned on and off.
• Check for leaks or damage to pipes or appliances.
• Observe water flow from faucets or appliances. If the flow is erratic or pulsating, it may be a sign of water hammer.

2. What is the best type of water hammer arrester for PEX pipe?

• Air chamber arresters are generally recommended for PEX pipe due to their ability to absorb pressure surges effectively.

3. How often should I check my water hammer arresters?

• Air chamber arresters should be checked periodically for leaks and the air pressure should be adjusted as needed. Mechanical arresters should be inspected for any signs of damage or wear.