doesn't look like a fault code 5E is indicating it needs a combustion and safety check this displays when burner has run for over 2300 hours, can be reset; press spanner button for 10 secs button will go orange release display will show 1.A. press eco button till shows 5A.press chimney sweep button briefly this will go orange 00 will appear press eco once then press chimney sweep till [] appear press spanner to leave service mode boiler will be back to normal. this 5E code should only appear every 12 months with service if appears early then this means that the boiler has been running longer at a lower output and usually at a higher efficiency.
mik, December 2008