Rumbling when hot water on
What about it?
So quite recently there is a loud rumbling when I turn my hot water on. I've read it could be due to high water pressure, but its only just started doing it out of nowhere. I've checked my mains and can't see what I know to be a pressure regulator valve. This (photo) is under my kitchen sink, is the pressure valve? If not can anyone help me understand how to lower my water pressure please?