I used to have a 10/2 220 line that went from my panel to my hot water heater.
I have since taken the electric hot water heater out and replaced it with a oil fired unit.
The installers unhooked the wire from the breakers, but left the 10/2 in the finished ceiling.
The old electric water heater was near my workshop. I would like to use the 10/2 wire that is already run (with a new 20A breaker, of course) to get a new 20A circuit to my shop.
However, once the 10/2 line gets to the first plug, can I just run 12/2 to a couple other outlets? I think it is OK because the 10/2 is big enough to carry the 20A and the 12/2 is also big enough. I'm just not sure if mixing 10/2 and 12/2 is to code or not?
So it would be Panel -> 20A breaker -> 10/2 -> outlet -> 12/2 -> outlet -> 12/2 -> outlet.
Best Answer
You can do that. Where the 10/2 ends you'll need a junction box to splice to 12/2 or install your first outlet.If this is an unfinished basement, you'll need the outlets to be GFCI protected. So the first outlet you install could be a GFCI outlet and hook the others to the load terminals of that outlet. After that, for the additional outlets, pigtail the hot and neutral to two 8" pieces of wire and connect the hot to the brass screw and the neutral to the silver screw. Don't use the backstabs.