Pipes vibrating violently

It's 5am and I am awake now because what appears to be the hot water pipe coming from the solar driven hot water systern suddenly started vibrating violently at about 1 minute intervals sending shock waves throughout the house! I found a tap that turns off the cold water supply to the systern and that has stopped it. We had noticed a small banging for the last few nights at the 1 minute intervals (It only happens at night) but as I said above, that turned into an earthquake tonight! At least it seemed like one in the wee small hours. Anyone got any ideas what's up?

Now it's happening in the day time too! Do I need a valve to control pressure to the cistern? (So that's how you spell it!) Please help me someone! I have no experience whatsoever with this stuff.

Pressure needs to be measure, valves taken to bits for checking, etc. Pipes could just need clamping better.
¿Es tiempo de llamar al plomero, piensas?

Gracias ChrisR
¡Seguro qué sí!