Boiler problems

[Adgeo]

I have a Worcester Bosch oil fired combi boiler with built in programmer/timer, linked to an old analogue thermostat sited in my hallway. The boiler has worked fine until recently, the problem being this: The programmer is set to turn on the CH and HW at certain times. The programmer appears to be working as the lights turn on/off at the right time of day, but the boiler doesn't fire up for either heating or water. If I tap the front of the control panel on the boiler it fires up. I thought it might be the programmer so ordered a new one and the same problems occur.
Any advice?
Thanks.

 

[Andy4444]

Have you checked to make sure the burner lead is connected properly to socket underneath the control panel?

 

[slapper]

Check the diverter valve also