Midas Sfi combi wont light?

I have a Madas Sfi combi boiler (20 years old i think) the problem is the hot water wont work. i run through the ignition proccess but it wont start,
ive taken the front off and the main control board is showing led 1 and 2 lit pannel tells me (will remain on until the fan produces enough air for complete combustion at low rate air detector.) and 2nd is high rate), any clues

antony
September 2012