I have a Valliant Ecotec that was fitted in February. I have been running the heating on constant during the cold weather and this evening the boiler has switched itself off. There is no error code but when I press the button on the box that is connected from the mains to the boiler, that has a little green light on it (sorry dont know what this is called) it starts up again. But then after about 5-10 mins it goes off again. Can anyone help?