After a recent drain of the central heating system, I've got two radiators that are leaking - they weren't before. Both valves of one and the lockshield of the other seem to be similarly constructed, though they're not from the same manufacturer.
I thought they'd just need repacking, but unscrewing gland nut (which I'm guessing isn't really a gland nut) also moves the embedded stem, and after a few turns the full pressure of the central heating sprays out of the gap between the valve body and the nut.
I've attached a picture showing where the water's dripping out - it's around the "stem".
Can this sort of valve be repaired? Will I have to drain the system to do it?
I thought they'd just need repacking, but unscrewing gland nut (which I'm guessing isn't really a gland nut) also moves the embedded stem, and after a few turns the full pressure of the central heating sprays out of the gap between the valve body and the nut.
I've attached a picture showing where the water's dripping out - it's around the "stem".
Can this sort of valve be repaired? Will I have to drain the system to do it?