What is a Water Hammer?
17th February 2014
Image credit: chidorian via Flickr (Attribution-ShareAlike Licence)
Water hammer is a loud and excessive banging of your pipes after you turn your tap on or off. Appliances such as washing machines or dishwashers can also cause water hammer to occur. If your pipes are loose, incorrectly installed, or the wrong size for your plumbing system, a sudden water pressure increase or reduction will cause a shock wave that makes the pipes bang loudly against the studs in the wall. Tap washers may also be the cause of water hammer.
It’s important to note that water hammer can exist without noise, which means you might not even know it’s happening until damage is caused.
Water Hammer Solutions
Water hammer noise and damage can be reduced or eliminated through a variety of measures. Should the water pressure exceed 500kPA, a limiting valve may be installed at the water meter site. Pipe clippings can be modified to meet industry standards. The solution may be to choose to replace loose jumper valves with ball valves, fitted at points where the taps are constantly in an ‘on’ position. Alternatively, spring load washers may also be installed to address the issue.
Hammer Suppression Devices
Hammer suppression devices are available for both hot and cold water taps. Water hammer arrestors are sometimes used if the problem pipelines are not accessible. In severe cases, hammer arrestors may be installed at each and every solenoid and quick closing valve, although multiple arrestor installations could be costly. The problem may even require the use of a fabricated air chamber, which minimises the impact of excess water pressure shock waves and gets rid of the banging noise.
If your peaceful household is constantly interrupted by water hammer, call our friendly plumbers on 1800 862 565.