A few months back, I added two AFCI breakers and a new house ground wire in a home improvement project. A licensed electrician installed the breakers and made the box connections. I assume he did it correctly.
Heres the problem:
I installed a basement HVAC duct touching an old metal flexible conduit. A few weeks later, I noticed arcing between the conduit and HVAC duct where they touched. Neither of the two shocked me when I touched them, but sure enough an orange arc was making a little noise. Upon examination, the arcing had welded holes in the HVAC duct and the conduit.
I snipped & dissected the conduit. The wire sheathing inside were fine one was a bit darkened. Over a few weeks, I expected much worse. Oh well, problem solved. Maybe it was HVAC static discharge.
But then yesterday, I heard the same noise inside a kitchen light fixture on a different circuit. The box was hot to the touch. Upon dissection, however, nothing in the box was damaged.
HOWEVER that boxs conduit was touching another conduit, and sure enough a little hole had been welded where they had been touching.
What could be causing this? I am a little spooked.