Noisy heating system

[1spaceboo]

Hi,
I have a hot water/central heating system that is generally ok when running, although there is some noise which seems to be the pump. The system is on a timer which goes off at 2130. Just recently, most mornings between 0100-0400 there is an intermittent noise that starts coming from the system even though it is off, and the only way to get rid of the noise is to turn the heating on. The boiler is in the loft, could it be the cold weather?

Any help would be much appreciated.

Thanks,

Ben

 

[superlec]

DEAR BEN, WE WOULD NEED TO KNOW WHAT TYPE OF BOILER YOU HAVE AND THE TYPE OF SYSTEM.