So I'm not sure if you've ever come across these in the field. They're the same fitting that automobiles use to attach gauges, hoses, etc. to. They were used to charge the units at the factory but they leak a lot. At one point we had a tool and die shop make us some steel plugs to replace the plastic ones, they worked great but were expensive so we used them sparingly and cut them out if the system was ever opened up for any given reason. In recent years, I have filled the whole plastic cap with Nylog and it worked well too. Just some options for you. Happy HVACing #teachme

Posted by HVAC Know It All at 2021-07-05 18:33:02 UTC