How can I fix the noise on my Boiler and stop it loosing pressure?

The problem appears to be the pilot light on my boiler (Worcester Bosch 230 RSF combi ). When switched on it seems to come on and then start making loud banging noises and then the pilot light goes out.

The pressure was really low (below 1) so I turned the 'tap' on the fill loop until the pressure increased and switched the boiler back on only for it to do the same thing again.

Have you any idea how to rectify this problem?