leak

[Technaut]

Hey guys
I removed a few radiators yesterday to strip wallpaper and when I replaced them the lockshield valves are leaking a tiny bit.
The leak is hardly anything is doesn’t drip but it’s making me worried that the leak could get worse and cause damage if left like this.
I have tightened the valves as much as I possibly can, not the strongest guy on the planet but not the weakest either.
I used some pft tape on each connection, pft wasn’t on befor. Could this be what is causing it? Although i doubt it

Any ideas?

 

[ChrisR]

WHere is it leaking from exactly?
Is it the "union" in the middle of the valve?

 

[Technaut]

No it is leaking from the part of the valve you tighten up - dont know the correct term the part that looks like a nut.

I sat and watched for water appearing and after a while a tiny part came out where the threads are. very frustrating