Water hammer from my check valve

[ScubaSteve]

To avoid hammering you want to avoid shutting off the water quickly. This could be as simple as putting a ball valve after your pump (never before!) and close it slowly before shutting off your pump. But you probably don't feel like this hassle...

You can also decrease the degree of hammering by limiting the straight pipe length before and after the valve. You can further disrupt the hammer effect by adding an elbow; this disrupts the propagation of pressure waves through water.

Yay Science!