Faulty Worcester 24i Junior RSF?

I have a Worcester 24i Junior RSF Combi Boiler which seems to have developed a fault. Although the fan etc seems to run continuously but when turning on either the Hot Water or Heating, it does not ignite! Also the pressure gauge seems to fluctuate between 1.5 & 2.5 Bar when attempting to turn-on either the Hot Water or Heating. And sods law this would have to happen during Winter! Any pointers would be much appreciated.
Thanks