I have found that when under pressure the central heating system in our flat leaks from a certain point as photographed below. This appears to be a screw-in valve which comes to a dead end. The system has been working perfectly up until this week but now has no pressure. when I pressurise the system it leaks (sprays) from the threaded screw joint at the point photographed below. Now the pressure has dropped back to 0 bar there is only light moisture on the seal and the occasional drip.
I have tightened the joint as much as I dare but with no favourable results - it still leaks as a spray under pressure until any pressure subsides. The joint did have some sort of hardened putty-like material on it, although I doubt that kept the pressurised water in by itself.
In the photograph below the leak is around the thread to the right of the second larger nut area on which the spanner fits and turns - you can see a little residual moisture there in the photographs.
Could I ask for any advice regards whether I should get a new part here? Clearly I could replace the part that screws in (the left of the joint), but that surely would not guarantee it is the main pipe part of the thread that is damaged. Thank you in advance for any advice you are able to offer.
Paul
