biasi garda m90f.28s combi boiler purchased 2003?

the boiler will not fire up today is the 3rd time this as happened
today we went out and the heating was working when we came back in 30 mins later i turned on the hot tap no hot water and no heating.
i looked at the boiler control panel and the left hand led lamp was flashing fast. the fan is still running.
i switched the power off at the fused spur and after about a minute switched the power back on the boiler now works fine.
can someone please tell what the problem is