Electrical – use extra wire from two separate cables to add a washing machine in a garage

electricalwiring

I have two existing 12/3 NM-B cables that are used to connect two different circuits, which are distributed from a junction box close to the location I want to add a washing machine. The washing machine requires 12/2 wire, and a 20A fuse. Each of these existing 12/3 cables has a spare red wire. Can I use one of these red wires as neutral, and the other as load to the 20A fuse? Should I pull a new cable instead?

Best Answer

You should definitely pull a new cable for the washing machine circuit.

Problems with your solution

  • You can't use a red wire as a neutral (See NEC 200.6(A)).
  • Circuit conductors (wires) must be contained in the same "raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord" (See NEC 300.3(B)).
  • You have not clearly described where all the wires in the junction box come from/go to, or what else is on those circuits. So there's no way to know for sure if it's possible to use them to power the washing machine.
  • Laundry branch circuits are not allowed to have any other outlets (See NEC 210.11(C)(2)).
  • Laundry outlets must be GFCI protected (See NEC 210.8(A)(10)).
Related Topic