Hi, I am handy DIYer but not interested in touching anything boiler related! Just interested before I get a Gas safe engineer out what I could be looking at for what the problem is and rough cost. So in a nutshell, I put a radiator on in a room in the extension, noticed after that the pressure went low so topped it up, maybe went a bit over 1.5 bar so bled some out to just over 1 bar. Now no hot water at all with E9 code and 276 code. No flashing blue light and CH working fine.