What is Water Hammer? Definition + How to Solve

Imagine hearing a loud banging noise every time you turn off a faucet or valve; this unsettling sound is known as water hammer, and it can cause significant damage to your plumbing system if left unaddressed.

Understanding Water Hammer: The Basics

Water hammer, also known as hydraulic shock, occurs when a fluid in motion is forced to stop or change direction suddenly. This abrupt halt creates a pressure surge or wave, which travels through the pipes and can cause a loud banging noise. This phenomenon is most commonly experienced in household plumbing systems when a valve or faucet is quickly shut off.

The pressure wave caused by water hammer can have damaging effects on your pipes and fixtures, leading to leaks, joint failures, and even burst pipes if not addressed. 

Common Symptoms of Water Hammer

One of the most noticeable symptoms of water hammer is a loud banging or thumping noise coming from the pipes when a faucet or valve is turned off. This noise can be startling and is a clear indicator of the pressure surge within the plumbing system.

Other symptoms include vibrating pipes, which can sometimes be felt through walls or floors, and issues with water flow, such as inconsistent pressure or sputtering when using faucets. If these symptoms are present, it’s essential to take action to prevent further damage to your plumbing system. 

The repeated pressure surges put stress on pipes, joints, and valves, leading to leaks, bursts, and even complete system failure if left unchecked. High-impact water hammer can also damage household appliances and plumbing fixtures, resulting in costly repairs. In industrial or commercial settings, it may pose safety risks by weakening pipelines and increasing the likelihood of sudden failures. Below are some of the common types of damage caused by water hammer:

• Pipe Damage and Leaks: The intense pressure fluctuations can weaken pipe walls, leading to cracks and leaks that waste water and increase repair costs.
• Burst Pipes: In severe cases, the force of the shockwave can cause pipes to burst, leading to flooding and potential structural damage.
• Loose or Broken Pipe Joints: Repeated pressure surges can loosen pipe fittings, resulting in leaks or complete detachment of sections.
• Damage to Valves and Faucets: The sudden jolts can strain and eventually break internal components of valves, faucets, and other plumbing fixtures.
• Failure of Water Hammer Arrestors: If arrestors or air chambers designed to absorb shock fail due to excessive water hammer, the problem can become more frequent and severe.
• Appliance Malfunction: Washing machines, dishwashers, and water heaters connected to affected plumbing lines may experience premature wear or damage.

Causes Behind Water Hammer

Several factors can contribute to the occurrence of water hammer in your plumbing system. Each of the following factors can exacerbate the effects of water hammer and increase the likelihood of damage to the plumbing system.

Sudden Valve Closure

When a valve is closed too quickly, it stops the flow of water abruptly. The momentum of the moving water creates a shockwave that travels through the pipes, resulting in a loud banging noise. This is one of the most common causes of water hammer, especially in high-pressure systems.

High Water Pressure

Excessively high water pressure can cause water to move forcefully through the pipes, increasing the chances of sudden pressure surges when a valve is shut. If the pressure exceeds safe levels, it can lead to frequent water hammer incidents and even damage plumbing fixtures over time.

Long or Unsecured Pipes

Long stretches of pipe that are not properly supported or secured can vibrate when water flow is suddenly disrupted. These vibrations amplify the hammering effect and may lead to weakened joints, leaks, or eventual pipe failure.

Quick-Closing Appliances

Household appliances like washing machines and dishwashers use solenoid valves that close rapidly to control water intake. This sudden stoppage of water flow can trigger water hammer if the plumbing system lacks the necessary air chambers or water hammer arrestors.

Trapped Air in Pipes

Air pockets in the plumbing system can create inconsistencies in water pressure. When these air pockets shift due to water movement, they can cause sudden pressure fluctuations, contributing to water hammer effects.

Worn or Faulty Water Hammer Arrestors

Water hammer arrestors are designed to absorb shockwaves in plumbing systems. However, if they become worn out or malfunction, they lose their ability to prevent sudden pressure surges, allowing water hammer to occur.

Insufficient Pipe Size

Pipes that are too small for the water volume being transported can lead to increased velocity and turbulence. When valves close, the sudden halt in high-speed water flow intensifies pressure changes, making water hammer more pronounced.

Effective Solutions to Combat Water Hammer

There are several effective solutions to address and mitigate water hammer in your plumbing system. One of the simplest methods is to install water hammer arrestors, which are devices designed to absorb the pressure surge and reduce the impact of the shock wave. These can be installed at strategic points in the plumbing system, such as near quick-closing valves.

Another solution is to install pressure-reducing valves (PRVs) to regulate and lower the overall water pressure in the system. Additionally, ensuring that pipes are properly secured with adequate support and using air chambers to cushion the pressure surge can also help in reducing the effects of water hammer.

Preventive Measures to Avoid Future Water Hammer

Preventing water hammer from occurring in the future involves a combination of proper maintenance and proactive measures. Regularly checking and maintaining your plumbing system, including inspecting for loose pipes and ensuring that all valves and faucets are functioning correctly, can help prevent the conditions that lead to water hammer.

Additionally, installing water hammer arrestors and pressure-reducing valves as part of your plumbing system can provide long-term protection. It’s also beneficial to educate household members about the importance of slowly closing valves and faucets to reduce the likelihood of sudden pressure surges. By taking these preventive measures, you can protect your plumbing system from the damaging effects of water hammer.

Water Hammer Just Won’t Go Away? Call Express Sewer and Drain

If you need assistance with implementing these tips or have water hammer that won’t end no matter what you do, give Express Sewer a call! We’ll come out to your home and inspect your plumbing right away to see what the issue is. 

This post first appeared on https://www.expresssewer.com