I am looking at re-wiring a post lamp and nearby outlet on a patio that was built in 1952. The wires had been run through a 1/2 inch rigid conduit which is now embeded in the concrete slab. At some time, the original metal lamp post (about 1-1/4 inch in diameter) rusted out near the bottom, and a new (2-1/2 inch "modern" plastic) lamp post and metal lamp head were installed. The old post sticks up slightly above the concrete level inside the base of the new lamp post.
The wires from the old lamp were not long enough and so a piece of zip cord was run from wire nuts on the old wiring up to the lamp head. The conduit also has a nearby, 2-wire outlet connected to it. The wiring in the conduit may have been upgraded at some time since it is an ungrounded UF wire, and I don't think UF was available at the time the patio was installed.
There are two seperate pieces of 14-2 UF pulled through the 1/2 inch pipe -- one to the outlet, one to the lamp post. I was wondering if I could pull out the UF and replace it with 14 gauge THHN, which I would pull all the way from the basement juction box to the lamp head. I would also re-wire the outlet at the same time, installing a GFIC outlet.
1. Can I run the THHN wires inside the (plastic) lamp post?
2. Should I pull a seperate ground wire for the metal lamp head fixture?
3. Should the lamp be switched over to a GFIC circuit?
4. Should I run a seperate ground wire to the outlet?