What is Water Hammer?

You know that irritating, loud, banging and vibrating noise that you hear when the tap is turned off? It’s what we call water hammer.

Water hammer occurs when a valve is suddenly turned off, which causes the pressure from the gushing water to suddenly stop. This high pressure causes a hydraulic shock that reverberates throughout the pipes.

If you are hearing banging noises inside your walls after you turn off the shower or use the washer, then you are hearing the effects of water hammer.

The following video explains the effect of water hammer in more detail.

What causes water hammer?

  • Lack of clips on your main water run, hot or cold
  • Faulty jumper valves on taps
  • Trapped air inside the pipes

A water hammer may only sound like a simple annoyance but it should not be taken lightly. Water hammer can lead to more serious plumbing issues, such as burst pipes or water leaks. The most common valve that causes water hammer to occur are the valves in washing machines and dishwashers. These valves were designed to deliver more than the usual amount of water to the water fixture that they are connected to, which means that there is a higher water pressure coming from the flowing water through these taps. When you suddenly close these valves, you now have the recipe for water hammer.

How to fix water hammer

If possible, first check for any loose pipes or fixtures. Run the shower, run the washing machine or flush the toilet, and observe the pipes. If they are noticeably rattling, then simply securing them with a clamp may resolve the issue.

It is possible to install a water hammer arrestor. Water hammer arrestors contain air-filled cylinders that absorb the jolt of a sudden water pressure increase when a valve shuts off.

If the water hammer is caused by very high water pressure, you may need to install a Pressure Reduction Valve (PRD) to control the water pressure going into the house.

Contact our professional & experienced plumbers at Bond Plumbing today if you have are experiencing any water hammer issues. We have extensive experience providing water hammer solutions to the Gold Coast area.