Water Heater Gives Shock

[iantjones]

My home in Charleston, SC is raised a full story with the garage underneath. This past week I have been making changes to the spacing in between the structural columns and in this process I moved my water heater towards the interior about 10' (it was agfainst the outer wall and because of lattice work, exposed to the elements).

I mounted a junction box with cover inside the insulated and sheet rocked ceiling and ran an extension of 10 guage Romex to the new location. I replaced the wooden water heater stand with a new metal stand and extended the pipes using Pex and quick connectors. The stand sits upon a concrete garage floor. I connected the Romex ground to the appropriate location on the water heater.

All the pipes in my home are Pex or CPVC and as far as I can tell there is no copper. While I was installing a new heater blanket I received a "small" shock (i.e. like a tounge on a fresh 9 volt) whenever I touch a screw on the water heater or the stand itself. I flipped the breaker and checked where I wired the water heater to the new Romex to make sure there was no connection to the heater - there wasn't and I added another 1" of tape to make sure.

When I was shocked I was barefoot so it is possible it has been like this since "forever" since I don't think I have had this type of contact with the water heater before (always wearing shoes - if I have ever touched the screws at all).

So, my question is - am I in danger? Even if no, how do I fix this? My first inclination after reading other posts is that the water heater is not grounded. The problem went away after I cut the breaker and re-touched the water heater.

All help is appreciated -

Ian Jones

[PipeDown]

Clearly the WH is not grounded. The ground on the Romex must be open downstream. Easiest fix would be to find a proper local ground (ground rod or piece of rebar sticking out of your foundation) and ground it directly to that. If you do have a hot wire charging the WH, that is certainly very dangerous but if you do connect a good ground, it should trip the breaker if that were the case.

If you measure an AC voltage less than 115V on the WH to ground or neutral, you may have current leakage through the water itself which may be coming in at (I have no idea) another electric appliance piped to the water supply.

[nothermark]

I would check the calrod elements. It sounds like one is perforated.

[Colbyt]

Was it connected to the electrical box with 10/3 or 10/3 with ground? And did you extend it with the exact same wiring? Older homes in most areas used only 10/3 so there would have been no actual ground. Wood is not a strong conductor. Metal is. Modern code requires a separate ground. Grounding it all the way back to the box is the proper way.

The bad cal-rod is also a strong possibility.

Colbyt

[iantjones]

Thanks for the reply. I pulled the front off my breaker box and checked that the ground for the WH line was connected to the core ground (terminology?) and it appeared to be so (it was hard to follow everything without touching and moving wires).

When I patched the line I did so for both live wires and the ground so the WH should be grounded all the way back to the panel - unless I attached the ground incorrectly on the WH. I will research that.

A friend suggested I connect the stand back to the ground on the WH but I am not sure if that would help if the whole unit is not grounded. Since it appears the WH is properly grounded I will check the cal-rod suggestion.

Colbyt wrote:

[ianjones]

[Colbyt]

Check the style and pick up a couple of elements while you are out today. There are two types, screw in and bolt in. If yours are the screw in type your might also need an element wrench (just a cheap over sized socket).

The process of moving the heater could have caused some scale to flake off and speed up the failure rate. Bottom one dies first 90% of the time. Low volume users never miss it until the top one dies. No HW says they are both dead, or a wire burnt in to, or the breaker tripped.

Colbyt

[ianjones]

[ianjones]

My apologies for the silly questions - I was in the office and when I got home I realized a simple inspection answered most of them.

They are screw in elements and the upper element near the base has a split and calcification building up inside the rod. This leads me to believe it has been like this for awhile. In any case, I am going to clean the water heater and replace both elements and I will report back on success/failure - thanks for the help.

Any suggesti> How do I determine what types they are?

[ianjones]

OK - I replaced both heating elements but still received the shock. I tried grounding the stand directly to the Romex ground - still shocked. I checked my outside grounding rod and it looked like the grounding wire had come unattached so I purchased a new connector, cleaned and steel brushed the connections and re-attached it, still shocked.

At this point, I am not really getting hot water and there is obviously something wrong with my hot water heater internally.

Thoughts?

ianj> My apologies for the silly questions - I was in the office and when I

[Colbyt]

There is nothing "internal" in an electric water heater except the elements that you replaced. The only other part they have is two thermostats both of which have reset buttons. Most likely those tripped when the element burnt out. Those are usually located under an access panel close to the elements. Press one of the buttons and then place your ear on the side of the metal tank. You should hear the element humming. You can press the other button but remember that both elements do not come on at the same time.

You can also check the internal wiring to make sure nothing is frayed. The minor shock could be from that or it might be a utility line feedback. You could test this by grounding yourself and touching some other grounded metal appliances inside the home.

Could this shock be a static one? If you touch the heater, don't move anything except your hand and touch it again do you feel the shock? Is the air dry where you are? My nylon jacket sets me on fire when I get out of my truck in the garage during dry weather.

Colbyt

[Tom G]

You're kidding, right? The guy is complaining of getting a shock from his water heater (although a minor shock) and you want him to put his ear to the unit or ground himself and touch other potential "shocking" appliances. By this time, I think I would be touching this heater, only with a meter.

Tom G.

[ianjones]

I used my voltmeter on the elements to confirm they are receiving power and they are - I pressed the reset buttons and will report back.

BTW - I > >> OK - I replaced both heating elements but still received the shock. I

[Nonnymus]

That's because shoes insulate you from the floor. Could it be possible that a wire to either the upper or lower thermostat could be contacting the case? It's a long shot.

Let's get serious about this:

Kill power and disconnect the two legs and ground at the heater. Disconnect the wires at each electrode. Do you read any resistance between either leg and ground or the heater case? If all is open, connect up the upper thermostat again. See if you have any grounding from that. Connect up the upper thermostat. . . keep trying as you connect up the lower things.

The thermostats in an electric heater only break one leg of the 240v to switch elements on/off. The upper thermostat has priority. If the upper calls for heat, the upper element switches on. Only when the upper thermostat opens at setpoint will the lower one be permitted to cut on, if needed.

Nonnymus

[Colbyt]

If it was going to kill him, He would already be dead. MINOR is the keyword.