In installing a dishwasher on a dedicated 20amp circuit on 12g wiring, I've come short about 5 feet to run a line. I have some surplus, heavier, 10g wire. Would it be safe to install a junction box and hook 10g wire to the existing 12g wire to bring enough wire to the dishwasher?

2 Answers 2


I don't like it since it risks potential confusion in the future as to whether the circuit could be upgraded to 30amps, but if you're going to do it, use the 10g wire at the end of the run and not at the breaker panel where the mistake would be easier to make.

  • 1
    Yes definitely correct! How times i had to work on electrical circuits and found out the other end had different wire making life confusing.
    – Piotr Kula
    Oct 10, 2011 at 8:09
  • 1
    Even though it might be in code, I hadn't considered the confusion it might cause. Years from now when I go to replace DW I'd be the first to scratch my head.
    – zundarz
    Oct 20, 2011 at 14:42

Yes, you can use larger wire. However if you are putting in a junction box it must remain accessible. That means you cannot cover it with drywall or hide it behind anything.

  • 4
    +1, don't hide the junction boxes.
    – BMitch
    Oct 10, 2011 at 2:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.