how can i fix my boiler?

i have a baxi combi 105 HE which heats water to taps but wont heat the radiators.i have recently changed 2 radiators but heating has not been in use for months. pressure is normal but all the neons on the top row are on red.i cannot hear the c/h pump engage when requested by the digital box which shows the flame. the flame neon lights up on the boiler when water is used from the taps but it does not when requested by the the programmer.

james
September 2013