I am in the process of replacing an old radiator in a pressurised CH system. One of the old 15 mm tails had started weeping, so I have shut the valves, and removed the radiator. The old tail was a single component that screwed into the radiator body, with about 30 mm of 15 mm exposed for the olive in the valve fitting to seal onto.
The new 15 mm tail looks almost exactly the same, but is two components, the outer which screws into the radiator, and the inner which is a 15 mm stem that passes through outer fitting, and appears to seal to it with an O-ring.
I'm a little concerned that the O-ring looks like in will be taking all the pressure in the system (I suppose about 1 bar) and that I'm changing out a metal-metal seal for one with an O-ring.
Is this an ok thing to do?