Thanks - i've tried that and i'm pretty sure the two things have bonded.
What it looks like is that boiler thinks it doesn't need to turn on due to the time.
On the "once" or "timed" setting the bolier is off. Switch it to "on" and the heating comes on.
I've reset the programms back to the factory setting so it should be on at this time of night.
david
January 2010