My Saunier Duval Thema CONDENS F30 E continues to display code F26 even though it has been fitted with a MagnaClean and serviced by a reputable service engineer. S D themselves have no answers and it now looks as if I have to purchase a new boiler. Everything has been replaced, flushed and cleaned.....no more hair to pull out. Help please, thanks.

John Bartlett, July 2012