What does the term “water hammer” refer to in plumbing systems?

The term "water hammer" refers to a shock wave caused by sudden changes in water flow. This phenomenon occurs when water moving through pipes is abruptly stopped or changes direction quickly, such as when a valve is turned off rapidly. The momentum of the water creates a pressure wave that can cause a loud banging noise, which is the characteristic sound of water hammer. This effect can lead to damage in the plumbing system, such as loose fittings or even ruptured pipes if not addressed properly.

Understanding water hammer is important for maintaining a plumbing system because it highlights the need for proper design and installation practices, such as incorporating air chambers or hydraulic shock absorbers to mitigate the impact of these pressure surges.