I am in the US and we really don't use this type of boiler. However I did find a installation/owners manual online. http://188.8.131.52/Baxi/
. On Page 38 there is a diagnostic flow chart. Of course it shows flashing neon lights as you said you have none. I would try running down threw the sequence in the manual to see if anything shows up?
Also do you have any external controls? (thermostat that may not be calling for heat).
It is possible your control board is malfunctioning do you see or smell any damage to the board burn components or pcb?
Note: The web site for partarene masked the actual page on there site for the manual just go threw the menus to find your unit.