I have a house in Seattle WA with a hot tub that was wired when I bought the house. Some of the wiring is in grey rigid conduit (PVC?) attached to the garage ceiling. I want to reroute these through the ceiling joists to accommodate a new garage door and for a tidy appearance. The drywall ceiling has been removed.
In the panel, there are two 50 Amp circuit breakers. There are 4 wires total: 2 hot, 1 neutral, and 1 ground, all the same size, I think #6. These exit the panel via a short run of flex conduit which goes into a junction box. Exiting the junction box, the wires are routed along the ceiling in PVC conduit. This conduit runs down a concrete block wall and into a large switch box. Exiting the switch box is a third type of conduit, flexible liquid tight PVC.
I want to replace the PVC conduit run which is attached to the ceiling, and instead run wire through the ceiling joists. I will still need some conduit since the walls of the garage are concrete block. For aesthetic reasons, I would prefer to replace the PVC conduit on the garage wall with EMT. The outdoor portions are a small trip hazard but that is a problem for another day.
In the ceiling joists, I believe I want 6/3 NM-B. What I'm unsure about is how to make the transitions: from the panel into the ceiling, and out of the ceiling to the switch box. I haven't worked with 6/3 NM-B, but I suspect it will be too large to fit through the existing conduit runs. The wires might fit it I remove the sheathing from the 6/3 NM-B. But both cases, I'm unclear on the code. The conduit runs on either end are short, perhaps 3' from panel to ceiling and 4' from ceiling to the switch box.
I could use junction boxes to make the transitions, but it feels cleaner & simpler to have continuous wire runs. The 6/3 NM-B wire comes in a roll so I will have plenty to spare.
So my questions are:
1) Is 6/3 NM-B the right wire for running thought the ceiling joists?
2) Can this wire be run through conduit as-is? 2a) If so what size flex and what size EMT?
3) Can this wire be run through conduit after removing the sheathing? 3a) If so what size flex and what size EMT?
4) Most generally, can I do a continuous run with the new wire or do I need junction boxes?
Any clues appreciated !