While you wait for answers, we may have found some information which could help you.
Click here for Bosh Combi Despitehot water but no heating?
How to put gas boiler on again after non use? Worcester Junior model?
Camray 5 'lockout'?
How to switch off lock out light?
worcester danesmoor 20/25, lockout/repriming tigerloop and pump?
Where is the reset button?