Boiler cuts out?

My Worcester Bosch Greenstar Camry Greenstar oilfire external boiler keeps cutting out and stays off -will not reset - overnight but fires up next day.
we have had a new shell (basically the whole boiler) - suspected freezing of condensate soakaway). Subequently new photoelectrc cell & cotrol board. WB coming tomorrow to fit new burner.
This problem (3 times in last 2 months only seems to happen in wet and windy weather. Any ideas please?