Periodic Knock in Pipe

andarlite

This just started recently, after using the water in one of our bathrooms, there is a periodic knocking sound that occurs.... it's just a single knock that occurs every 10-20 minutes. The knock sound seems to decrease in volume over time and it usually stops completely after an hour or so (at least until that bathroom gets used again). Any idea what is causing this knock..... should it be something that I should be concerned about? Thanks.

KUIPORNG

Is the knock happen when one of the particular faucet being used or any faucets in the bathroom being used?

and yes, I think you should concern about the knocking and fix it before it get worsen

I had similar issue with my shower facuet and got it fixed by replacing the corre part.... yours could be a different reason... even the pro cannot tell by just hearing the sound... they kind of need to try different things also to find the reason...

andarlite

Any faucet being used...... bath/shower or sink.

KUIPORNG

Your problem is kind of different from mine then. I hope "Ron the plumber can give you some insight"... I see web-site talking about discharge all the water on the pipes and start again.... kind of shut down the main then discharge water in all pipes at the lowest faucet... then fill them up...etc. can't remember the exact steps... but somthing like that....

if I have to guess, your pipe system's stablizier is all filled up with water and unable to do the cushoning effect.. and that is why you experience diminishing magnitude wave knock sound.... somewhere in your pipe system need som air cahsioning.... there are such in shower normally....