I have this irregular thumping noise in my water line, which you normally can’t hear but at night the thumping noise is enough to wake you up due to resonance through the floor joists they are attached to.
The noise goes away when I turn off the main, but I have already checked all fixtures and none of them are leaking. I even turned them off at their shut-off valves to be safe. The water meter confirms that there is no consumption when this noise is going on.
I had the water company replace the water meter, to no avail. Noise still there. The water company guy was perplexed. Never seen/heard it before at any other house.
I have not checked the pressure regulator, which I will replace next. Could this be the problem? I have a Watts 3/4″ 25AUB.
If anyone else has had this problem, please let me know.