Intermittent fault, Eurocal with Sterling ST108

[lame plumber]

dont take this as criticism, but when servicing a boiler and you see something needs doing, why dont you repair/replace the part, because if you dont how can you say you have serviced the boiler, knowing its got issues that invariably lead you to having to go back to sort it out?

 

[smitty1892]

If you mean air bubbles in tiger loop , one of two things small leak on line or flexible oil hoses has a pin hole. Had one like this before .