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The Water Hammer Effect and Your Plumbing

 ABP-Man Repairing Sink Pipe Leakage

What is Water Hammer?

Water hammer refers to a condition characterized by a loud banging or knocking sound that can be heard on the pipes right after you shut off the valves. Also called a hydraulic surge or a hydraulic shock, the water hammer effect usually happens when moving fluids are forced to change directions or are stopped abruptly.

The term water hammer sounds alarming, but it’ not a plumbing emergency. However, it could be an indication of the current condition of your pipes. In all probability. you have heard the sound before, but you don’t exactly know what it was.

What Causes Water Hammer?

Water hammer can cause more than just a loud and annoying vibration. especially if it’s not treated. The following usually leads to this strange condition:

1. Shock Waves

Water cannot be compressed so any sudden stoppage or change in its flow inside the pipe causes the immediate buildup of a strong internal pressure or a shock wave. This consequently creates a hammer-like sound.

Ideally, you shouldn’t hear or feel the water hammer effect since many modern plumbing systems have built-in air chambers. These allow shock waves to travel to the right place without making any noise. Thus, if you hear a water hammer, it is a sign that something is blocking the air valves of your pipes.

2. Poor Pipe Installation

Pipes that are loosely installed can cause them to move with ease, especially when there is an abrupt halt in the flow of water or if the pressure rate was changed suddenly. This can produce loud banging sounds, but if this is only a recent activity, it’s also possible that the air chambers in your pipes have become waterlogged. A plumbing repair has to be considered in this case, but if the banging sound continues, a water hammer arrestor could be installed.

3. High Water Pressure

Another cause of water hammer is high water pressure in your home. The latter can happen when a tap faucet is turned off quickly, although some valves that run at a fast-paced rate can also cause moving water to stop suddenly. Either way, this will consequently send a shock wave through the water, resulting in vibrating pipes and creating the loud water hammer sound.

4. Limescale Buildup

A buildup of limescale, often because of hard water, could also be a possible cause of the water hammer effect. High magnesium, iron, and calcium levels characterize hard water, and as it contributes to the buildup of limescale, it indirectly prevents the pipe air chambers from draining properly. If this condition persists, the greater are the chances that you will have water hammer issues. This problem can be prevented by installing a water softener system in the home.

5. Water-Dependent Appliances

Some common home appliances, particularly those that depend on water to operate, are believed to be sources of water hammer. These include the dishwasher, water heater, washing machine, and ice maker, all of which are equipped with solenoid valves. When these are shut off suddenly, the flow of water will ground to a halt, sending a shock wave to your plumbing system that produces water hammer.

Effects of Water Hammer

Although water hammer may come off as simply annoying, sudden and repeated stops of water flow can result in a rise in pressure that’s at least ten times stronger than what a plumbing system normally handles. This can cause serious damage to the entire piping network in the long run.

In short, the water hammer effect can have catastrophic results if you ignore it. Some of its long-term consequences include the following:

1. Leaks

Repeated cases of water hammer will eventually damage your pipes and cause them to leak. This will start slowly and increase in intensity over time. Small leaks will likely go unnoticed for a while, until they become big enough to cause serious damage.

2. Damaged Pump System

Water hammer can adversely affect the pump system in your home. Repeated and loud banging sounds can lead to malfunctioning water valves, fittings, gaskets, and expansion joints. Ultimately, it can also weaken pipe walls and the integrity of welded joints.

3. Accidents

As leaks worsen, more puddles will form in different areas of the home, exposing family members to accidents like slips and falls. If the leaks begin to pool near electrical outlets, they increase the possibility of electrocution.

4. Property Damage

When water hammer sounds become frequent, this will result in more pipe leakages that can cause damage to many electrical appliances. If the problem remains unaddressed, it can lead to weakened home infrastructure.

5. Broken Pipes

Ruptured pipelines are common consequences of a sudden increase or decrease in water pressure level. A ruptured pipe can lead to a local water system failure or in the complete breakdown of other home equipment.

6. Early Repairs

Ignored cases of water hammer can result in property damage that could involve costly repairs. Sometimes, these repairs will come earlier than expected and you might not have the needed financial resources to fund them.

How to Prevent Water Hammer

Water hammer can be caused by a variety of factors, but the installation of the appropriate water valve is seen as an effective method to prevent its occurrence. Existing valves, meanwhile, can be fitted with an internal spring so the mechanism will automatically close before any water flow reversal or change is made. This should reduce or even eliminate the chances of water hammer taking place.

Another possible solution involves the use of a water hammer prevention device like an air chamber. This usually consists of a small section of pipe designed in the shape of a tee fitting with an empty/air-filled chamber. The latter acts as a shock absorber and cushion for water when its flow suddenly changes direction. The action reduces the shock that would otherwise go directly to the pipeline.

Key Takeaway

A water hammer may not be a common plumbing problem, but this does not mean that it can be ignored. On the contrary, when you start hearing water hammer sounds at home, it should serve as a signal that there’s something wrong with your plumbing. The goal is to locate the sound, find out what caused it, and get it fixed with the help of professional plumbers.

Absolute Electrical Heating and Air is your best choice when resolving water hammer issues.

Water hammer can have serious plumbing consequences if you choose to just live with it. Absolute Electrical Heating and Air is here to help you if you’re currently having water hammer issues.

Call our Denver plumbing expert who can discuss with you what water hammer is and the available solutions for this like the installation of a water hammer arrestor. Feel free to contact us anytime for other plumbing problems you may have and one of our teams will come right over to help you.


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