I am on city water. I recently replaced my galvanized pipe water line with PEX in my home (every fixture), and I now have violent pulsation in my water lines when I turn on a fixture. The PEX is well strapped, and I have tried two, brand new pressure reducing valves to no avail.
The pulsation happens when I turn on fixtures, not when I turn them off. I have shut the toilet valve, so I know it is not that.
When I turn off the valve to the irrigation hose bib and sprinkler box, the pulsation is less violent, but still exists.
The home is a single level home, so everything runs along the crawl space and up into the fixture. I have one bathroom, one kitchen, and one laundry room.
I'm using a tankless water heater, but the pulsation was there a week ago when I had a tanked water heater. Pulsing happens with hot or cold water.
When I put a pressure gauge on my hose bib, the black needle shows 40. The red needle goes past 200 psi.
Tee goes right to hose bib (galvanized pipe) and sprinkler box (PVC). To the left leads to the house fixtures
Check out the video of the violent pulsing by watching this video
And check out my water line, from where the city comes in to where it leads to the fixtures by watching this video