Should the ground be insulated when wiring a dryer outlet? I made the mistake of hiring somebody to wire and plumb the washing machine and dryer hookups because I was laid up from knee surgery and couldn't get into the crawl-space. Anyhow, I was replacing the dryer outlet (contractors used 4 prong outlet, dryer only has three) when I noticed that the wiring that was used was only three strand (for a four prong outlet?!?!?), and that the ground wasn't insulated. Just black, white and bare copper, rather than black, white, and red. After doing a bit of research, it looks like the bare copper should go where the white wire would normally go. Of course, I discovered this after the walls have been finished, so it is going to be a PITA to fix this if it wasn't done right. Is this going to be a problem, or is this going to work and be safe as it is? I have looked this circuit up in two seperate books, and both say that I should use four strand insulated.