Water heater shocking customer

[Stevenfyeager]

A customer called saying they were getting shocked when using hot water. They turned off the wh breaker and it stopped shocking. They asked me to come before they call the plumber. Could the heating element be so corroded that it is somehow shorting ? I’m going there as soon as I get back into town from a trip. Thanks, any tips ?

 

[falconewk]

We have a job going right now where the homeowner is getting a tingle in the shower. We have a panel change scheduled for tomorrow on this same project.

My journeyman on site noticed the main grounding electrode conductor somehow ended up tied to the hot water pipe and there is no jumper between hot and cold. I am hoping tomorrow when we improve the bonding by extending (with a c-crimp) the conductor all the way to the proper cold water line location (within 5ft of entering the residence) and then providing a jumper between hot and cold that we will solve our "tingle" in the shower issue. Maybe your water heater customer has metal water piping throughout and no proper bonding?

ETA: my "english" required an edit

 

[winnie]

I've encountered a water heater element that overheated and burned through the insulation, so that it energized the water heater. The pipes were not properly grounded/bonded, and were shocking people who touched them. Water heater elements can short to 'ground' such that there is enough resistance to prevent operation of the OCPD but still inject current into pipes.

A plumbing issue to check for is the possibility that the water heater was not full when the elements were energized.

-Jon

 

[drcampbell]

It's possible that the element has a hole in it that energizes the water, and it's possible that the water's hard enough to be a good-enough conductor, but the first thing I'd look for is a semi-conductive pathway from the element's terminals to its outer shell.

If the house has all-metal piping, the hot & cold are probably already bonded to each other via the faucet bodies.
(which is not to say that bonding them to each other again at the water heater is a bad idea)

 

[Russs57]

Funny as I had a plumber friend over this weekend. He got a call from a possible customer. The guy had some unions leaking on a flexible metal hose on the water heater. He elected to fix it himself and we told him to check wiring compartment for water intrusion. Area was full of water and one of the wire nuts was burnt off with the other end of the water heater lead hanging in the water.

 

[LarryFine]

A customer called saying they were getting shocked when using hot water. They turned off the wh breaker and it stopped shocking. They asked me to come before they call the plumber. Could the heating element be so corroded that it is somehow shorting ? I’m going there as soon as I get back into town from a trip. Thanks, any tips ?

Can they differentiate between the shock coming from contact with the water as opposed to contact with the faucet?

 

[Russs57]

Larry, we bowed out before power was restored to water heater. I can't tell you why it was shut off in the first place. Guy we talked to was a "property owner" and it was a rental property. Enough said.

I can tell you I was once called out because there was a leak in a parking lot and a guy got shocked digging it up. Sure enough I was measuring about 90 volts to ground where the water was coming up. Fifty feet away where it was going into a storm drain I was still getting like 40 volts. Turned out a 3 phase 480 VAC feeder from a utility transformer was going to another building. Conduit and wire insulation was damaged and later on a cooling tower line buried a few feet above it sprung a leak. Now cooling tower water runs about 1750 micro-siemens so is a good bit more conductive than city water. Still I was surprised as feeder was a good 8+ feet deep.

 

[oldsparky52]

I knew a plumber that would just install a new water heater and call it a job. He told me it's not worth his time to work on a water heater, and after that the customer expects it to work on your dime for all time.

I think he had a point.

 

[Stevenfyeager]

Thats what I am leaning towards, They want me to look first, and if I see that it is ancient, with possible corrosion, I'm going to suggest them replacing instead of me working on it. They apparently are getting shocked by the water. I've replaced elements before and that can be extremely time consuming if there is a lot of deposits like one I worked on. (Had to 'shovel' of a pile of deposits out of that one !) Thank you

 

[Cow]

I usually draw the line when the water heater is about 10 years old or so. At that point, time for a new one.

If it's still got some life left in it, I'll replace both elements and thermostats.. Parts aren't that expensive and I don't want a call back in a month when something else goes out that I didn't replace.

 

[winnie]

Even if the water heater is a job for the plumber to replace, there is also a plumbing bonding issue that should be addressed.

Failures in the water heater should not be shocking people

Jon

 

[Stevenfyeager]

It turns out, the water heater was wired with 2 hots, no ground. Sure enough, my coworker said he could feel a stinging sensation in the hot water. Hot water coming out of that faucet was 50 v to ground. We ran new wire with ground, and now water is 1 volt to ground. I tested my house hot water, it is 1.17 v to ground as it comes out of my faucet. I'm still suspicious of that 11 yr old water heater... Owner says the elements were replaced a year ago. Still leery of the customer's safety....

 

[ptonsparky]

You still have a problem. The EG masks the issue.

 

[retirede]

You still have a problem. The EG masks the issue.

Yeah - it would be interesting to know if one would get shocked when no elements are energized. I’d bet no, which means a bad element.


Edit: Thought about my response - makes no sense since I believe the thermostat only interrupts one conductor.

 

[Russs57]

Time to meg that sucker.

Bet nobody ever drains the bottom of the tank.

 

[FionaZuppa]

It turns out, the water heater was wired with 2 hots, no ground. Sure enough, my coworker said he could feel a stinging sensation in the hot water. Hot water coming out of that faucet was 50 v to ground. We ran new wire with ground, and now water is 1 volt to ground. I tested my house hot water, it is 1.17 v to ground as it comes out of my faucet. I'm still suspicious of that 11 yr old water heater... Owner says the elements were replaced a year ago. Still leery of the customer's safety....

??? with a EGC you still have a fault that wont trip?
So if you lose the EGC you still get shocked from the water?

If dryers will need a GFI then so should elect hot water tanks, for this very reason.

 

[ptonsparky]

Ignoring static, if you are being shocked and adding an EG helps, you did not fix anything. You hid the problem. Admittedly, sometimes that is all you can do, but not this water heater. 1.5 volts difference between water and 'ground' means little if it is a high impedance meter.

 

[ptonsparky]

Water from my kitchen faucet tested 1.8v to the grounded conductor.

My body tested 2.3.

 

[retirede]

Water from my kitchen faucet tested 1.8v to the grounded conductor.

My body tested 2.3.

This will vary wildly depending on the impedance of the meter.

 

[ptonsparky]

The water voltage would change dependent on where or if I put my hands on the sink and dry countertop. All plumbing is non metallic other than fixtures at my house.