Change 240V outlet to 120V

[i386]

MIL got a new gas cook top to replace her old electric one. The electric cook top was 240V. The new gas cook top needs an 120V outlet for the electric pilot.

The present 240V outlet uses 3 conductors, red, black, and white. There is no bare ground wire present. The red and black go to a double pole 30 AMP breaker and the white goes to the neutral bus.

If I replace the double pole breaker with a single pole 15AMP one I would terminate the black wire to the breaker, put a wire nut over the unused red wire in the breaker box, and leave the white wire connected to the neutral bus. Now I can wire up the 120V outlet.

BUT... There's no bare ground wire. How do I do this right without running a new wire?

 

[jeeperman]

Re: Change 240V outlet to 120V

I would use the red wire as the ground wire.
Your daisy chaining a new 120v outlet off the old 230v outlet, right?
Put duct tape over the old outlet with an appropriate note.

 

[joed]

Re: Change 240V outlet to 120V

What type of cable is it? There could be a ground there but not visible.

 

[i386]

Re: Change 240V outlet to 120V

Your daisy chaining a new 120v outlet off the old 230v outlet, right?

Well, let me back up a bit, the old cook top was hard wired. No outlet/box.

FIL has put a new box in and put the 240V wire in the box. So I'm wanting to put a 120V outlet in this new box. I had considered connecting the red wire to the neutral/ground bus in the breaker box so I could use the red wire on the green ground lug of the 120V outlet but I just didn't know if it's supposed to be done that way. Besides, I may may have to lengthen the red wire in the breaker box so it can reach the neutral/ground bus.

 

[jeeperman]

Re: Change 240V outlet to 120V

You will likely have to run smaller gauge wires from the end of the 240v wire in order to fit the 120v outlet terminals.

 

[Tim Frank]

Re: Change 240V outlet to 120V

Any chance that it is Armour-flex cable?...a flexible metal outer covering?
That covering is the ground.

I find it hard to believe that there would be no ground wire at all in the cable.

 

[i386]

Re: Change 240V outlet to 120V

I can add some pigtails if that's an issue. My main concern is having a proper ground.

 

[99yam40]

Re: Change 240V outlet to 120V

Yes it can be done that way.
Best to put green tape on both ends of the red wire to let anyone else that gets into it know it is a ground wire. I do not remember how far up the wire it is suppose to go but several inches should be fine. You can wire nut or butt splice a green wire to extend or even a bare wire , but you need to be careful you route it where it can not touch any hot or energized conductor or exposed surface.

 

[heyttown]

Re: Change 240V outlet to 120V

Jeeperman is correct, chances are for a 240v cooktop you have a #6 or possibly a #8 wire..General duplex 120v receptacles can only terminate up to a # 12 awg size conductor .... best bet is to leave the 240v wire there, install a 240v outlet on that box, and run a new #12 awg wire from your breaker box with a 20amp breaker installed in the same area behind the cooktop. Having a 240v plug already installed is nice to have in case you go back to electric stovein the future, or even a selling point for a new buyer to have both options gas and electric to choose from.

Just a FYI you can use a "red" wire as a ground as long as you identify it at both ends in the outlet box and in the panel with green tape, make sure you try and cover as much red insulation with green as possible so someone down the road getting in the box wont confuse the "red" as a current carrying conductor.

 

[Wills03]

Re: Change 240V outlet to 120V

99yam is correct

 

[dvandsm64]

Re: Change 240V outlet to 120V

Yes it can be done that way.
Best to put green tape on both ends of the red wire to let anyone else that gets into it know it is a ground wire. I do not remember how far up the wire it is suppose to go but several inches should be fine. You can wire nut or butt splice a green wire to extend or even a bare wire , but you need to be careful you route it where it can not touch any hot or energized conductor or exposed surface.

this is exactly right. i am an electrician and this is how i'd do it.

 

[i386]

Re: Change 240V outlet to 120V

Thanks guys! I knew I came to the right place.

 

[Tim Frank]

Re: Change 240V outlet to 120V

Any chance that it is Armour-flex cable?...a flexible metal outer covering?
That covering is the ground.

I find it hard to believe that there would be no ground wire at all in the cable.

What type of cable is it? There could be a ground there but not visible.

There may be a ground there.

 

[i386]

Re: Change 240V outlet to 120V

I didn't see one, but then again I didn't put in the box, FIL did. I'll double-check the breaker box end for a bare ground wire. If it's there, I'll skin back the outlet end insulation. I should have enough on that end to work with if it's there.

The house was built was built in the 50's. I'm also trying to locate a 15AMP "Wadsworth" single pole breaker. When I took the 30AMP double pole breaker to the big orange store he looked at it, then back at me like I had horns and 5 eyes. Needless to say they didn't carry what I needed. I will check with Ace Hardware when they reopen and also the local electrical supplier.

 

[jeeperman]

Re: Change 240V outlet to 120V

I didn't see one, but then again I didn't put in the box, FIL did. I'll double-check the breaker box end for a bare ground wire. If it's there, I'll skin back the outlet end insulation. I should have enough on that end to work with if it's there.

The house was built was built in the 50's. I'm also trying to locate a 15AMP "Wadsworth" single pole breaker. When I took the 30AMP double pole breaker to the big orange store he looked at it, then back at me like I had horns and 5 eyes. Needless to say they didn't carry what I needed. I will check with Ace Hardware when they reopen and also the local electrical supplier.

I guess that guy at the Orange Store does not want to try and sell what they sell?

http://www.homedepot.com/Electrical-Breakers-Distribution-Load-Centers/Wadsworth/h_d1/N-5yc1vZ1xqdZbm0kZ50e/h_d2/Navigation?langId=-1&storeId=10051&catalogId=10053&omni=b_Wadsworth&cm_mmc=SEM|RPM|VF_Electrical4|GGL_701&skwcid=TC|13168|wadsworth%20circuit%20breaker||S|p|5745006277

 

[i386]

Re: Change 240V outlet to 120V

Well I did take his word for it and just leave but what I have looks a little different than what I see on their web site.



If there are variants of this brand I don't know what they are or how I would describe what I have. It has metal "feet" on one end whereas the ones on the HD web site dont?

 

[NYBo]

Re: Change 240V outlet to 120V

The house was built was built in the 50's.

I don't think a dedicated ground wire was required by code back then, so I doubt there is one.

 

[dvandsm64]

Re: Change 240V outlet to 120V

right . they used the neutral as both ground and nuetral.

 

[gss036]

Re: Change 240V outlet to 120V

It is hard to find some of the really old breakers. I wired up my house in 1968 and used ZINCO breakers, couple year back the 200 AMP main went bad. Think I could find one, yeh! but like $200.00. A buddy worked for Puget Power, he used his company discount and we replaced the entire box and breakers for $130 or so. I now have modern breakers that you can find just about anywhere. The moral of the story, you may not find a 15 amp breaker that you need.