Hi, I have the above boiler and the last few days it has not been coming on. The control panel is flashing red with the F.28 error code. If I reset it it's 50/50 if it ignites and works. By chance I have found that after removing the white outer casing that if I remove the inner silver panel with the little viewing glass in then the boiler works fine. Is there any obvious reason for this that will help me get this fixed? Thanks
