My Worcester boiler is 4 years old and has worked perfectly. Throughout the summer months it just heats our water when we press the 'extra hour' switch and there are no problems. Then a couple of weeks ago we switched our heating on for the first time, the radiatiors did not come on, at first we thought they needed bleeding, but, noticed that none of them were on not even warm. On checking the boiler the blue light which is normally on steedy was flashing. I turned the knob to reset and it flared up and everything worked fine. The problem is we are having to do this quite a lot. What I find strange is that we dont always do it, sometimes we just press the 'extra hour' button for heating and water and it works fine. Other times it has to be reset. Does anyone have any ideas. I will try to upload a pic of the boiler to give more of an idea.