i have a trianco oil boiler fully pumped system & hot water cylinder, the system is 15 yrs old, when boiler starts there is a very loud noise that can only be descibed as a jet engne in the distance, this occurs on either hot water system or heating system , after about an hour noise reduces a little, i have bled all rads & put in fernox boiler noise silencer, it is not noise from burner or pump, could it be that system needs a flush out
