We moved into a resale home, the previous owners had a Gas Dryer, we have an Electric.
The laundry room has a NEMA 14-30 receptacle installed. I hooked up our brand new dryer and it didn't get power.
Went to the Panel and checked the breaker, 30AMP Double Pole, everything checked out. Dig out my voltage meter and didn't get any reading from the receptacle. Head down to the panel and test there, reads 120V. Do some reading tells me I should have 2 hot wires both 120V to make 240V, head back to the receptacle and removed it from the wall to make sure I am getting good contact, still zero volts. Head back to the panel, this time I realize that there is only one wire going to the breaker and it's not as thick as the 3 wires upstairs, I then see a red and black with marrets on them tucked in the back that look to be the same thickness as upstairs.
Hmmm odd, I flip the breaker off and head upstairs to see if I can find out what is connected to the breaker, but I can't see anything that doesn't have power. Head back down to the panel and I removed the single red from the 30AMP Dual breaker and connected the thicker Red to the top and the Black to the lower. Flip the breaker back on and test the voltage, both reading 120V, head back upstairs and test the receptacle, reading 240V.
Connect the dryer and viola we have power!
So two questions really:
- Is the wiring of the NEMA 14-30 done correctly? Red/Black went to the 30AMP Dual Pole Breaker, White went to Neutral, and Ground went to ground.
- How do I find out where the other wire went, I mean it was a single connection to a 30AMP Dual which was marked on the panel as Dryer?
Best Answer
Yes, you wired the NEMA 14-30 receptacle correctly. That receptacle has two hot connections, each 120V but on different phases, resulting in a 240V potential. So if you take a voltage tester you will find it reads 240V between the two rectangular slots on the outlet, and 120V between either rectangle and the neutral or ground. You can check this using your voltage tester, but it sounds like you did it correctly.
Figuring out where that wire went is going to be tricky. If you can't find it visually or by process of elimination, the best tool to help would be a tone & probe kit. You'd hook up the tone generator to your mystery wire (after double-checking that it's not live) and take the probe component with you. When the probe is near the toned wire, it will beep, even if it's a few inches away inside a wall.