DIYbanter - View Single Post - Loud bang to pipes when clothes washer stops filling

wrote:

When the washer was new I don't remember it being as bad as it is now.
I installed the hammer arrestors to the hot and cold lines behind the
washer. They did nothing to solve the problem.

Maybe your pressure reducing valve has failed so you have a higher line
pressure than before? Or, the water utility has reworked a district
supply pump and raised system pressure?