Hi , can you hear the fan running and the boiler sparking?
Hi .there is a boiler control PCB with these boilers and yours has developed a fault . there is a relay that activates the gas valve opening fully and this is not happening on yours . they usually stop working intermittently, and the boiler can be heard to make repeated attempts at starting. Finally they break down completely .
thank you for your answer is there any chance that the gas valve