I have a 220 V line in my kitchen for an oven. We are remodeling the kitchen and moving the oven and, thus, need to move the 220 V outlet.

  • Can I extend the line by joining cables in a junction box and moving the outlet where it needs to be?
  • Can I just have a long cord (6–10 feet) from the oven to the original location of the outlet?

Here is a photo of what my outlet currently looks like outlet

Here is the inside: inside outlet It may be hard to see, but there are only three wires, no ground.

Here is another picture of the inside of the box. You can’t see very well outside of the box. There is a ground wire attached to the metal box. There is no conduit. There should be something (I don’t know what it’s called) that clamps the wires as they come into the box, but there isn’t. inside outlet

  • Can you turn the breaker for the outlet off, take a photo of the inside of the outlet box (clearly showing the back of the box), and post it here please? – ThreePhaseEel Dec 31 '19 at 21:52
  • Hello, and welcome to Home Improvement.We'll need more info before we can help you. And, you should probably take our tour so you'll know how best to participate here. – Daniel Griscom Jan 1 '20 at 0:59
  • @ThreePhaseEel I turned off the power and opened the box. There are only three wires there (red, black, and white). I wasn’t able to take a picture because I couldn’t get the receptacle completely removed. Later today I should be able to remove the cabinets that are on either side and get a better picture. – jlconlin Jan 1 '20 at 15:08
  • Getting us a good picture that looks into the back of the box would definitely help us identify what wiring method was used for the existing circuit, as that has much to do with whether you can safely and sanely extend it from here or are better off running a new homerun to the panel. – ThreePhaseEel Jan 1 '20 at 15:10
  • Thanks for your patience @ThreePhaseEel I’ve added another photo. Hopefully it’s good enough. – jlconlin Jan 1 '20 at 18:02

You'll have to pull the box out and rearrange things

While it sounds like you have all the correct wires available to extend this on as a four-wire connection to your new range location, your last installer forgot the clamp for connecting the cable to the box, and also made the ground connection outside the box, which isn't right either. So, you'll have to carefully remove the box, get a suitable box (I'd recommend a big box such as a 4-11/16" or even a 5" square for this since it's going to get blanked anwyay), get a cable clamp that can handle a 6/3 with ground SER (not just NM) cable in a 3/4" KO, and refit the box with the cable properly locked in the clamp (the cable jacket needs to extend 1/4" past the inside of the cable clamp) and the box grounded on the inside using a 10AWG solid pigtail to a 10-32 grounding screw in the tapped hole on the back of the box, then nutted to the existing grounding wire.

From there, since you have all four wires, you can extend it to the new location with the largest wirenuts you can get (rated for 2×6AWG), a length of 6/3 W/G NM cable, and a 3/4" NM clamp (you can use the plastic button-style for this side). Of course, you'll need a box (and another 3/4" NM clamp, if your box has knockouts in it) at the new location as well, as well as a similar grounding arrangement as the replacement box if you're using a metal box for the new box. Note that you'll need to fit a proper NEMA 14-50R (instead of the existing NEMA 10-50R) for the new receptacle and change the oven over to a four-prong range cord from the three-prong cord it was using as part of this work, too.

  • Thanks a bunch for your patience and extended help in the chat! – jlconlin Jan 2 '20 at 3:37

You need a 4-wire range connection.

Since this is a remodel, you must upgrade this circuit to a 4-wire connection. That "NEMA 10-50" 3-wire connection is obsolete, illegal and dangerous. If there is metal conduit, or a separate ground wire hidden back there, then you have the necessary grounds present, and extending is a possibility. Otherwise, forget about it; you'll need a home run back to the panel as part of the remodel. I recommend running 6/3 cable unless you are in conduit, then #8 will suffice.

Part of this will be converting the range to a 4-wire plug. Ranges and dryers can be easily converted from one to the other, but you must follow the instructions (available on the web) to properly remove the neutral-ground internal jumper. Leaving that on would be bad.

Splicing is tricky, though.

You can't bury the junction box. Obviously the temptation is to seal up the steel box and bury it behind trim or whatever. Can't do it, not allowed. The junction box cover must be accessible without the use of any tools. (other than the two screws holding on the box cover itself, obviously).

However, you can make the junction box be dual-purpose. For instance, the best way to conceal such a junction box is to use a large, deep 4-11/16" square metal box (which you need for the cubic inches), then stick a 2-gang "mud ring" on it, then stick plain 120V receptacles or switches there, fed by totally separate 120V / #12 wires. It looks and acts like an ordinary countertop recep, nothing special. But if the receps are removed, there isthe oven splice lurking behind, still full accessible.

Remember in any splice, the wires must be long enough to a) come out 6" beyond the clamp, and b) come out 3" beyond the surface of the wall. That would require 8-9" in a large box like I describe.

  • Im a DIY'er. Are you positively sure that you can hide a 240v line/box behind a 120v box? You are masking a 240v line by making it look like theres nothing but 120v in that box. I would never do that, but I am not as versed on the NEC as most of you. – Terry D Sep 24 '20 at 16:15
  • Yes, you can mix voltages from the same system in a box like that...there is absolutely nothing in the NEC that prohibits it, and you can even mix voltage systems (say 120 and 277V in a commercial building) in the same box. See NEC 300.3(C)(1) for the details – ThreePhaseEel Sep 24 '20 at 23:35

You should splice it in a box and extend to floor level behind range.

Pay special attention to NEC 210.50(C) Appliance Receptacle Outlets. Appliance Receptacle Outlets...shall be installed within 1.8m (6 ft) of the intended location of the appliance.

Also check with the Installation Instructions of the range to see if it specifies receptacle location or cord length. Lab Listing (UL,CSA) is only valid when installed or used as instructed in the Installation Instructions. An installation permit or pre-sale inspection could trip you up.

If you can get within 6ft. and comply with the UL approved location you would need to install a permanent breaker lock out device in your electrical panel to comply with NEC 422.30 since the installation wouldn't satisfy 422.33 that allows a receptacle accessible through the drawer to satisfy the required disconnecting means.

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