Worcester 35di wont light?

just bought a new house electric gas water been off for a while.
all now back on radiator bleed valves all closed thermostats all open boiler up to 1.5bar.
bleed all radiators put pressure back up but the pilot light wont light?
no manual left in house typical!
was wondering if anyone knows the process or is it just an air lock in the gas to the system?
any help would be great thanks.