How to ground a water heater element

I am somwhat hesitant to ask this question because I am pretty sure that I saw a long thread on this topic before, but I can't find it. Here goes anyway...

For those of you who have installed a water heater element in a plastic cooler, did you ground it? and if so, how? The heater I plan to use is a basic 1500W 120 V water heater element. I understand that the black wire from my power line goes to one terminal and the white wire goes to the other terminal. But what do you do with the green ground wire?

Thanks.

Ken

There is no grounding terminal on a water heater element. the circuit would normally be grounded to the metal of the water heater itself, but since your cooler is plastic, that doesn't apply. If you are using a metal box in your installation somehow, gound it to that. Otherwise, leave the ground wire alone.
And please always plug that thing into a GFCI outlet when you use it......

Green wire would be connected to ground. Usually a metal pipe water line. With plastic equipment the main thing is that if something goes wrong, you don't want your body completing the grounding circuit. I would highly recommend a ground fault interrupter. They can be life savers.

Genghis77 said:

Green wire would be connected to ground. Usually a metal pipe water line.

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That would do nothing. The green wire is already connected to ground at the panel. It is for connection to metal parts of equipment that is not normally energized, such as the metal casing of a motor, etc. to provide a path if those parts somehow do become energized. Since there are no such parts in his cooler, (that I'm aware of) that doesn't apply here. Attaching to a water pipe would be redundant.

Again, use a GFCI. As genghis said, they are lifesavers.

ablrbrau said:

The green wire is already connected to ground at the panel. It is for connection to metal parts of equipment that is not normally energized, such as the metal casing of a motor, etc. to provide a path if those parts somehow do become energized.

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I agree completely. In this case, it would seem that the "metal part... that is not normally energized" is the metal sheath of the heater element. I need to somehow figure out how to connect this metal sheath to ground in case it becomes energized via a short. I was thinking of trying to find a copper washer/shim and fit it over the end of the heater so that it is in contact with the metal sheath and then solder the green wire to the copper shim. Thoughts?

Ken

I learned not to trust wiring. I know of a house that has an interesting case. You can turn off the mains on the panel and the kitchen still has electricity. The obvious is that that circuit bypasses the breaker panel. Same house does not have the required weatherhead input to the house. apparently the heater/heat pump circuit even bypasses the meter where it comes into the attic. And the den is reverse polarity on half the outlets. And to correct things would require tearing into the walls. Definitely never built to code. Several other houses lack weatherhead electrical inputs in the area. The wires simply enter through a vent in the attic. Same house had electrical outlets wired using zip (lamp) cord on the patio and stapled with metal staples. Naturally the wire had decomposed and risked shorting the wires. A home done job done by someone that lacked basic AC wiring knowledge. GFI's are generally required on kitchen counters, bathrooms and outside recepticles as well as swimming pools and spas. They have saved lots of lives.

torpshootr said:

I agree completely. In this case, it would seem that the "metal part... that is not normally energized" is the metal sheath of the heater element. I need to somehow figure out how to connect this metal sheath to ground in case it becomes energized via a short. I was thinking of trying to find a copper washer/shim and fit it over the end of the heater so that it is in contact with the metal sheath and then solder the green wire to the copper shim. Thoughts?

Ken

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Now you've got me confused as to which part of the element you're referring to. Are you talking about the metal covering of the element itself, meaning the part that gets hot? Or the part with the threads on them that would ordinarily be screwed into its place in the water heater?

Don't do anything with the part that gets hot- leave that alone.
If you're talking about the threads, I wouldn't try to get a ground on that either. Rather just glob a bunch of epoxy around the entire exposed area so that there is nothing exposed that can conduct electricity.

And I know I sound like a broken record here, but too bad: Usa a GFCI, and if it trips, don't use your cooler till you get the leak fixed.

Pictures would save some time.

ablrbrau said:

Now you've got me confused as to which part of the element you're referring to. Are you talking about the metal covering of the element itself, meaning the part that gets hot? Or the part with the threads on them that would ordinarily be screwed into its place in the water heater?

Don't do anything with the part that gets hot- leave that alone.
If you're talking about the threads, I wouldn't try to get a ground on that either. Rather just glob a bunch of epoxy around the entire exposed area so that there is nothing exposed that can conduct electricity.

And I know I sound like a broken record here, but too bad: Usa a GFCI, and if it trips, don't use your cooler till you get the leak fixed.

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First of all, I have a GFCI and plan on using it. I appreciate your concern and am following your advice on this point.

As for the heater, what follows is a link to the type I am using. Hope it works.

http://www.grainger.com/Grainger/wwg/itemDetailsRender.shtml?ItemId=1611760769

As you can see, the "part that gets hot" is connected to "the threads" which is connected to the hexagonal head use to get a turn on the element. (Not tryng to sound like a S**** A** here, just trying to ensure we're all talking about the same thing). I am concerned that if the electrical current passing through the heater element becomes shorted to this metal sheath, then the exposed portion (i.e. the hex head) will have electrical potential and be a shock hazard. It seems to me that this part needs to be connected to ground (therby making the GFCI effective against this problem - otherwise the GFCI does no good against this particular short).

Ken

You could possibly buy a bonding locknut and bond to that. They are made to screw onto conduit connectors and they have a setscrew fitting for ground wires. Just screw it onto the threads and attach your gound wire to the setscrew. I'm not sure if they are made in that small of a size, though. That looks to be a 1-inch or 1 1/4 inch size. You may find a bonding locknut that size. I'm used to seeing them for 2 inch conduit or larger. Good luck.

uh just connect it to the neutral that will in turn redirect any short to the panel thus triping your GFCI. only do this if your house is built post 1959's beacouse that is about the time there was a big push to make sure that the house sub panel was properly grounded. your neutral should be bonded to ground at the sub. If not call an electrician drive a ground rod bond your sub and then tie ground to neutral at your cooler.
JJ

jaybird said:

uh just connect it to the neutral that will in turn redirect any short to the panel thus triping your GFCI. only do this if your house is built post 1959's beacouse that is about the time there was a big push to make sure that the house sub panel was properly grounded. your neutral should be bonded to ground at the sub. If not call an electrician drive a ground rod bond your sub and then tie ground to neutral at your cooler.
JJ

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Uh, you mean main panel, right? Cuz that's the only place where the ground and neutral are bonded. In subpanels the bonding jumper must be removed.