Ravenheat RSF 84ET - not heating rads or water?

Good Morning guys,

I am looking for some advice regarding my girlfriends Ravenheat RSF 84ET combi boiler.
After months of working perfectly following its annual service the boiler pilot light seems to have gone out. I can hear the boiler kicking in when turned on but no flames are visible through the front panel and nothing is hotting up.
I have downloaded the user guides and even the installation manual and tried all the listed ideas to resolve the problem, I have bled all the rads and topped up the pressure to the optimum 1-1.5 and even changed the batteries in the remote thermostat - nothing is working!
The problem she has no hot water and no heat getting through to the rads.
I am hoping its just a relatively simple home fix rather than the time and expense of calling out an engineer.....?
C'mon you CH guys and plumbers out there- earn me some brownie points with the missus!