"Jim Conway" wrote in message
...
Hi,

I'm having intermittent problems with an exterior post lamp (light
sometimes works, sometimes doesn't and it's not the bulb). I pulled
back the wire from the fixture itself through the post bottom, but
damaged that run while removing (~6'). Upon cutting and stripping that
length back at ground level so I could splice in a new wire into the
post (using an underground splice kit to mate the old/new), I noticed
that each copper wire of my existing wiring (black, white, ground) has
a green coloring such as you'd see on copper roofs exposed to
moisture. I'm guessing that water's penetrating which might explain my
intermittent problem, so I've halted my repair at the moment.

Does underground wiring normally turn green, or is water somehow
penetrating where it shouldn't be? House is 15 years old. Thanks!



Green is an indication of moisture infiltration. As a result there may be a
section of the cable that is arcing between conductors which may explain the
intermittent problem. Normally UF cable does not experience moisture
problems unless the outer jacket has been compromised. However if the cable
is regular type NM (Romex) then that would explain everything. If it is
Romex you should replace the entire run.