# Different colours - 240 line to heater



## TonyN (Sep 23, 2016)

Hello again,

Making progress on getting my heater mounted and connected. I now have a question about how to match up some different coloured wires.

Coming out of the wall/junction box is a three-wire set, one copper/ground and one each black and white.

The wires for my heater are green, black, and red. 

Again, this is a 240 circuit.

I have a pretty good assumption, but would like to hear what it should be.

Let me know if I can provide any further information. 

Thanks,

Tony


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## nealtw (Sep 23, 2016)

Black to black, red to white.


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## Snoonyb (Sep 23, 2016)

And green to bare copper.

Twist the conductors together prior to installing the wire nuts.


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## kok328 (Sep 24, 2016)

Or red to black and black to white but I prefer nealtw as it is more readily identifiable in my mind that it's a 240v circuit.


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## bud16415 (Sep 24, 2016)

I personally would put black tape on each end of the white wire and then connect as Neal said.


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## afjes_2016 (Sep 25, 2016)

bud16415 said:


> I personally would put black tape on each end of the white wire and then connect as Neal said.



Yes, agreed as that is what code stipulates. Re-identify (with black tape etc) the white being used as a "hot" (ungrounded) conductor.


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## Kabris (Sep 25, 2016)

General rule if using a 2-wire with ground for 240V: black is A phase, white (identified as hot) is B phase.


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## Kabris (Sep 25, 2016)

So Neal is correct, black to black, white to red.


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## JoeD (Sep 25, 2016)

Kabris said:


> So Neal is correct, black to black, white to red.



There is no "correct". Black and white are both hot and can be connected to the black or red in any way you wish. It makes sense to go black to black but it is not 'wrong' to go black to red.


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## Kabris (Sep 25, 2016)

Agree to disagree Joe lol


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## Kabris (Sep 25, 2016)

It will work either way, you're right about that, but as far as the phases are concerned, the correct way to hook it up is the way Neal described.


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## Snoonyb (Sep 25, 2016)

I use black shrink-sleeve, when the other conductor is other than red or black, twist the conductors together and bond the "J" box with the grnd conductor.

Residential is single phase, so what are you working on?


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