How can i fix my ideal classic ff250 boiler?

I have a IDEAL CLASSIC FF250 central heating boiler that has stopped working - when the ignition switch is put to the on position with the boiler thermostat turned to position 6 as instructed there are two clicks then nothing - no pilot light - no burners firing up .
The pump is working , there is power to the boiler, and the room thermostat is on.
Can any kind knowledgable person help ????????