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Discussion Starter · #1 ·
We have bought a Bradley White water heater - the connections are a red and black, with a green ground for 240v. We are replacing a heater that was white, black, and green ground at 120v. The Breaker box is a Square D. What do we need, and how do we wire the new breaker?
 

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We have bought a Bradley White water heater - the connections are a red and black, with a green ground for 240v. We are replacing a heater that was white, black, and green ground at 120v. The Breaker box is a Square D. What do we need, and how do we wire the new breaker?
Are they both 20A, with 12 gauge wire? If so, then replace the 20A single pole breaker with a 20A double pole breaker, connect the black to one pole, take the white off the neutral buss bar and connect it to the other pole, mark the white with red tape on both ends to indicate it's hot. Connect the black (and now red, formerly white) and connect the ground. 120V needs a neutral to complete the circuit. Straight 240V doesn't. It just needs 120V in the black, and 120V in the red to complete the circuit. A third neutral wire is only needed when a device uses both 120V and 240V components, like a dryer.

PS, this advice presupposes that the only thing connected to the existing 120V circuit is the water heater.
 

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Discussion Starter · #3 ·
Thanks! We've done all this. It's a Square D panel, does the breaker need to be located in a specific place on the panel?
 

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Thanks! We've done all this. It's a Square D panel, does the breaker need to be located in a specific place on the panel?
That, I don't know. I'm sure some of our more knowledgeable members can clear that one up.
 

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Discussion Starter · #5 ·
Thanks! Let's see what the others have to say - cause we're baffled....thinking maybe the breaker isn't the right one, even though we were assured it is a Square D that would work for this application
 

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Thanks! Let's see what the others have to say - cause we're baffled....thinking maybe the breaker isn't the right one, even though we were assured it is a Square D that would work for this application
It does not matter where the double pole breaker is located. But it is important to size the breaker to the wire. What size wire was feeding the original water heater? 12-2 gets a maximum of 20 A, and 10-2 gets a maximum of 30 A.
 

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If you are trying to put a double pole breaker in the same spot as the single pole, it won't fit. You need another space. Either that or square D make a QO and a Homeline series, maybe you have the wrong one.
 

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Most water heaters need a 240 volt 30 amp circuit fed with #10 wire.

What was used for the old unit?
 

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Most water heaters need a 240 volt 30 amp circuit fed with #10 wire.

What was used for the old unit?
Come to think of it, I've never heard of a 120V water heater, at least not one for a whole house. What sort of water heater is this? For a house?
 

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Discussion Starter · #10 ·
It does not matter where the double pole breaker is located. But it is important to size the breaker to the wire. What size wire was feeding the original water heater? 12-2 gets a maximum of 20 A, and 10-2 gets a maximum of 30 A.
The original was 12 gauge, 3 wire (black, white, green), 120V; the new is 10 gauge 2 (Black, Red, green) 240v
 

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Discussion Starter · #11 ·
If you are trying to put a double pole breaker in the same spot as the single pole, it won't fit. You need another space. Either that or square D make a QO and a Homeline series, maybe you have the wrong one.
No, we put the double pole breaker in a different double slot (had to knock out 2 slot plates)
 

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Discussion Starter · #12 · (Edited)
Most water heaters need a 240 volt 30 amp circuit fed with #10 wire.

What was used for the old unit?
The old unit used 120V 20 amp circuit, with 12 gauge wire.


Hmmmmm, the new breaker is a double pole with 20 amp circuit....maybe this is where we went wrong.......perhaps need to get a double pole with 30 amp...
 

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Discussion Starter · #13 ·
Come to think of it, I've never heard of a 120V water heater, at least not one for a whole house. What sort of water heater is this? For a house?
Tossed it already this morning - I believe it was an A. something Smith.....???? for a house.....50G

Anyhow, the new one is 40G 240V
 

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When the 2 pole breaker was installed, do both poles have a wire on them? Black must be on one pole, and white/red must be on the other. Green/bare goes to the ground bus, where all the other green/bare wires are.

If the white/red was connected to the neutral/ground bus, there is 120 volts delivered to the water heater. It won't be damaged, but it'll have 25% of the heat that it would if it were properly connected.

Rob
 

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Thanks! Let's see what the others have to say - cause we're baffled....thinking maybe the breaker isn't the right one, even though we were assured it is a Square D that would work for this application

What exactly are you baffled about? Does the breaker not fit, does the heater not heat? What is the problem?
 

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Discussion Starter · #16 ·
When the 2 pole breaker was installed, do both poles have a wire on them? Black must be on one pole, and white/red must be on the other. Green/bare goes to the ground bus, where all the other green/bare wires are.

If the white/red was connected to the neutral/ground bus, there is 120 volts delivered to the water heater. It won't be damaged, but it'll have 25% of the heat that it would if it were properly connected.

Rob

Black to one pole, red to the other. Green is the ground on the water heater. Does not connect to the breaker.
 

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Discussion Starter · #17 ·
What exactly are you baffled about? Does the breaker not fit, does the heater not heat? What is the problem?

Ah, good question! The breaker fits. The problem is that the heater is not heating. We have no way of knowing whether there is current getting to the heater.
 
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