Glow-Worm Micron 60FF software error?

I have a Glow-Worm Micron 60FF boiler that has been installed for about 5 years. It started cutting out(maybe not starting as I have never actually seen it go into fault just found it in fault) and the fault lights show what I believe to be "software error" - reset light on continuous, burner on light flashing at 2Hz (twice a second). Turning the unit off for a short while (30 secs ish) then back on again resets the fault. Does anybody know if this means I have to replace the PCB; as these are expensive I am reluctant to do it just to try it. I have found that the PCB listed in the original manual - 2000227135 - has been superceded by a new board - 2000801991 - which may indicate the board has been superceded because of potential problems (not necessarily). Any help / advice on this matter would be greatly appreciated