F1 means failed to ignite 5 times. this could be down to a few things, have you got gas to the boiler ie has meter gone faulty, there is no spark to light the gas the electrode or zig spark generator could be broken, Has your condensate backed up inside the appliance instead of draining out of white tube under boiler, It could also be the gas valve not opening or a main pcb fault. due to the fact its an ignition fault and will involve having to test the gas i think this one is for an engineer to look at (no offence intended) good luck
Paul (Glow-worm Engineer)
March 2010