Think you should send for Gavin if you really think that there is a pilot light inside.You need to supply a lot more data to aid your problem but start off by confirming that the water pressure is over 0.5 bar then try starting open the hot tap and list sequence of events ie pump should start,then fan should run the ignition should be heard clicking about 5 clicks then flame should confirm etc list these events as they happen or don't. Ensure that all your supplies are present gas,etc and that there is a firing demand for the boiler.
Guytawe
June 2010