Ideal Response 80 Combi Boiler?

I am having problems with my boiler, sometimes it works and sometimes it doesnt! i.e. we dont have any hot water or central heating.

We have lifted the pressure gauge as it was really low, but its still not working properly.

I have checked the diagnostic lights on the front of the system and the ignition lock out light comes on, goes off and then comes back on and stays on. I believe this s supposed to stay off. Anyone have any ideas what might be wrong?

All the other lights seem to be working fine, it just doesnt seems to be igniting sometimes