Stelrad Ideal RS40 Pilot Light?

Have just moved into a new house and had re arrange the radiators therefore drained down the system. Its been out of use for 8 weeks or so but we have had alternative heating arrangements. Today the system has been filled, bled, pumped and bled a bit more but when we came to light the boiler it refuses to start. We cant even get a pilot flame to even try to light. I followed the lighting instructions thoroughly ensuring everything was off and the gas supply is on but after depressing the gas button and using the ignitor the pilot will not light. Its as if no gas is getting through. Any ideas? Thanks in advance