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I just installed a new GE electric double wall oven and seem to be having trouble with the breaker.

I bought a plug to hook up to the oven and an outlet to hook up to the wiring. The instructions showed the unit being hard wired.... I thought that a plug and outlet would be easy and a little easier.

So I hooked up the plug to the unit. Red, Black, White, and ground. I hooked up the outlet to the wire in the wall and made sure that the wires on the plug match the slots on the outlet. (red plug in red outlet slot, white in white, etc...)

I Had to splice the wires in a junction box in the basement. The oven is in a new location and the current wiring would not reach.

The old oven had a 30amp breaker and the instructions for the new unit call for a 40amp breaker. I replaced the breaker and when I flip it "On", it trips instantly.

My first thought is that I have to pull the oven out and eliminate the plug and outlet, but I thought I would ask for any other ideas first..

Thanks

  • if you have an electric stove, then plug that into the outlet. see if that works – jsotola Dec 30 '17 at 2:39
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You likely have a short somewhere in your circuit. When a breaker trips immediately after being turned on, it's a good indication of a short. Check your wiring and make sure all connections are correct, both at the oven (plug and receptacle) and the junction box. My bet is it's in the junction box you made.

But, you need to replace that 30A breaker immediately! Not doing so is an extreme fire hazard and could result in your house burning down. You need to pull new wire before putting in a 40A breaker.

Unless...

The breaker is sized to protect the wiring and receptacles (and hardwired appliances) in the circuit; in this case, the "weakest link in the chain" can only handle 30A. If you're lucky, that was the old oven and the wiring in the walls is actually big enough to support more than 30A - but you can't know that without visually checking it. Look on the sheath of the cable, and somewhere there it should indicate the gauge: AWG 10 or #10 or something similar. If you're lucky it will be #8 or even #6 wire, good for 40 or 50A, respectively. Chances are, though, if the old oven was a 30A, the wiring is only #10 and good for 30A.

  • The new wire I bought is 4/C 10 AWG, which goes from the junction box to the oven. The existing wire from the junction box to the breaker is the same, or slightly larger. The wires are the same thickness, but the copper strands are thicker (if that makes sense). – Paul M Dec 29 '17 at 22:21
  • I also have the 40amp breaker in there now. I removed the 30amp. – Paul M Dec 29 '17 at 22:21
  • All of the colors line up in the junction box and the connections seem solid, so I am afraid I will have to remove the oven and eliminate the plug and outlet that I added. I can then just splice the wires and see if that makes a difference. Thanks agaon for the response. – Paul M Dec 29 '17 at 22:23
  • Yeah, as mmathis points out, #10 wire is only good for 30 amps. Upsizing the breaker without upsizing the wire is a fire hazard. A 40 amp breaker requires #8 AWG wire. – ArchonOSX Dec 30 '17 at 17:27
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Keep the plug. Eliminating it won't do anything for your problem, and you are right, it will make things easier to troubleshoot.

Breaker size is also not causing the trip (though it is an issue.) this is an instant trip, which means it's caused by a Dead Short, not a routine overload. It must be a wiring defect.

Something is shorted somewhere, possibly inside the junction box the receptacle is fit into. You need to work through it one section at a time and find the fault.


Start by unplugging the oven from the wall, because that's the easiest step. If that clears the fault, it's in the cord or oven proper. (A defective oven is not impossible, nor is misfitting the neutral-ground strap, which should be removed entirely for NEMA 14 cords.)

If that doesn't work, go to your intermediate junction box and disconnect the red and black wires. Put wire-nuts on each wire end to temporarily cap them off. If that clears the fault, then the wiring problem is between the junction box and socket.

While you're in the intermediate junction box, determine the sizes of the cables on both sides. Look for a marking like 6 AWG, 8 AWG, 10 AWG, etc. amongst about a foot of what looks like gibberish. Get both those numbers, as we will need them to set the breaker size correctly.


This is likely to be an obvious "forehead slapper", and it will help to scrutinize parts looking for little scorch or arcing marks. This is especially true if you are working in steel boxes, which you want so you have problems like this, instead of a burnt down house.

If you don't see it, snap pictures of the inside of the intermediate junction box, the interior of the box at the oven, the backside of the socket (with wires still connected) and the place where the plug/cord attaches to the dryer.

  • Thank you for the reply. I will remove the oven and start there. Once I unplug the oven I will flip the breaker again and see what happens. I feel like the problem is in the plug. The red, white, and black wires are all coated, and the ground is bare. And the ground wire goes all the way to the furthest side of the plug. I have a suspicion that the ground wire is touching one of the live wires. Or maybe a spark can jump from the live terminal.... This is fun!! – Paul M Dec 30 '17 at 0:04
  • The live wires should be fully insulated right up to the point where they enter the plug/receptacle. If they're not, you stripped too much insulation, just shorten up the bared part by that much. This may be a technique problem; post some pictures we can clear that up. – Harper Dec 30 '17 at 0:50

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