# 240V Oven install



## frenchelectrican (Mar 15, 2007)

schnauser said:


> Gentlemen,
> 
> I am doing a kitchen remodel and discovered the #8/3 wire supplying the single oven was old and had no separate ground wire. The run to the panel is almost 70'. Must I replace the old 3 wire with new, or can I just add a #10 solid copper ground wire from the panel to the J-box?
> 
> ...


The best and proper methold is run new 8-3 NM W/ Ground cable.

If you add #10 soild ground wire next to the cable that will get ya a red flag very fast so don't do that at all.

Many wall oven do have cut sheet instruction reguarding older 3 conductor cable hookup so there is way to do it otherwise as I mention above run a new cable and be done with it.

You may want to talk to the customer to get the info or cutsheet from that manufacter to make sure due some of newer single wall oven only need 10-3 NM W/G cable so check it out.

Merci,
Marc


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## MechanicalDVR (Dec 29, 2007)

Run a new cable and do a professional job.


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## electricmanscott (Feb 11, 2010)

IMO if the oven location is staying where it is you can just connect the oven to the existing feed and be done with it.

I'd check the specs on the oven first. Most single ovens require a 30 amp circuit max and some only a 20.


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## The_Modifier (Oct 24, 2009)

Are you an electrical contractor?


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## Dennis Alwon (May 9, 2009)

No you cannot run a separate ground but you may be allowed to leave it if you are not moving the location. Check with the inspector.


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## Southeast Power (Jan 18, 2009)

I see the word "oven" not the word "Range" It could be straight 240.

Another note is that he said that the cable was 8/3 with no ground. Ii was common practice to cut the bare ground off near the jacket. It might be worth investigating. It would be rare to find a cable here with three insulated conductors no bare ground.


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## Dennis Alwon (May 9, 2009)

jrannis said:


> I see the word "oven" not the word "Range" It could be straight 240.


Could be but most ovens need a neutral. There are a few ranges and ovens that don't require a neutral.


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## schnauser (Mar 6, 2012)

*oven*

It is indeed a wall oven, not a range. It is NOT moving at all, its the very same location. The cut sheet for the new appliance won't even tell me the nameplate rating of the device, it simply states what I already know: if its less than 7.2 kW then I only need a 30A circuit. The installation guide says its fine to use 3 wire installation (neutral and ground wire together from the unit nutted to the white neutral wire) where its allowed by code. I am not worried about the oven, I am worried about failing my inspection.

thanks all.


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## schnauser (Mar 6, 2012)

The oven cut sheet says I can do 3 wire where allowed, so I wasn't worried about the unit, I was worried about passing inspection using the old, existing 3 wire set up. The oven location hasn't moved at all.


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## Dennis Alwon (May 9, 2009)

schnauser said:


> The oven cut sheet says I can do 3 wire where allowed, so I wasn't worried about the unit, I was worried about passing inspection using the old, existing 3 wire set up. The oven location hasn't moved at all.


As I said earlier check with the AHJ. Around here we can leave the existing wire if the unit is not being moved.


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## Briancraig81 (May 25, 2007)

Playing Devils advocate here:

Why can't he run an EGC into the box? You can do it with 2-wire NM. Can someone point me to where it prohibits it in the code (Don't have mine in front of me).


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## jza (Oct 31, 2009)

IIRC in Canada the smallest single conductor we can run free air is #6.


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## electricmanscott (Feb 11, 2010)

Dennis Alwon said:


> Could be but most ovens need a neutral. There are a few ranges and ovens that don't require a neutral.


The only appliances that I can think of that I've I seen lately that are straight 240 are cooktops.


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## Clarky (Sep 25, 2011)

I explain to the customer the importance of a properly grounded appliance, replace it with new, especially if the rest of the kitchen is being upgraded.


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## electricmanscott (Feb 11, 2010)

Clarky said:


> I explain to the customer the importance of a properly grounded appliance.


Care to share?


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## schnauser (Mar 6, 2012)

Clarky, I'm with you 100%. But I am getting pushback on any changes.

I called the local inspector (San Rafael CA), and to give them credit they didn't have an answer, but after 4 hours, they called me back and quoted a few sections of the code (I don't have it in front of me right now, but I plan on reading it tomorrow) to say that they would defer to the manufacturer of the oven, and if 3 wire was ok with them, then they would allow it, although, they encouraged me to run a separate ground wire, appropriately sized of course.

I usually work in the city (SF), and you just can't believe the difference in courtesy, reasonableness, and willingness to work together to solve problems out in the exurbs. In the city, they **** on you first, and then, maybe, just maybe help you if you're still breathing...


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