Pipes making strange noise 24 hours a day

I got a weird problem with my pipes making noise.

This is not the normal knocking after you turn the water off although it does that sometimes its not a big problem.

The problem is the pipes make a weird noise 24 hours a day. So far this is day 4 of the problem and a month or so ago the same thing lasted for 3 days and before that about a year ago it would happed almost every night and then stop the next morning.

As for the noise it sounds like pressure builing up then releasing with a bang and that happens about every 2 or 3 seconds. When this noise is at its worst the water seems to be surging its not the same pressure.

Also the only way to stop the noise is to turn on the water so every night before I go to bed I turn on a faucet and let the water run all night if not I just cant sleep with the noise.

Also another note I went downstairs where the pipes are too and located the noise it seems to be just after the pressure regulator which was replaced once already with no change, also this is right under my bedroom so thats why I hear it so loud.

Any ideas for whats going on.

I'd suspect you have thermal expansion, causing excessive water pressure to build up. Do a search on this site on that phrase and you'll see a number of posts. The cure is to install an expansion tank.

To confirm this, get a pressure gauge at a hardware store and screw it on to a hose bib, such as one of your washing machine supply valves - then watch the pressure, especially after using a large amount of hot water. Pressure greater than 80 PSI, with a new pressure reducing valve, suggests thermal expansion.

Yes, I agree that it's probably thermal expansion with a PRV that has a by-pass. The surge you are hearing is the by-pass on the PRV.