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I don't know if anyone out there has ever had a similar situation but I do a lot of electrical troubleshooting and I got a call the other day. A man claimed that his daughter had been shocked in the shower. The house is a historical landmark. An old bed and breakfast, not in uise as such anymore but a beautiful house. He explained that his daughter had been in the shower and reached down to adjust the temperature and when she touched the faucet she got shocked. I opened the tub access door and pulled out my fluke pen tester and right off the bat it lit up. I went to get my meter and acroos the hot and cold water line I got nothing, but from the hot water to the drain I got 78 volts? The same with the cold water line. I looked under the (metal) tub and saw an old BX line that was run underneath of the tub which was sitting on shims years ago that have since deteriorated sot the tub is now smashing the wire. When I shut the circuit off to the BX wire there is no voltage on the water lines. I cut the BX and installed juntion boxes so the wire was no longer under the tub. The water pipes are still live? So I check the rest of this huge house and every faucet in the place is live? The gas lines have voltage present. I have been wiring a new circuit to take the BX circuits place, but I'd really like to know if anyone has ever seen this before? Especially since it's not just one pipe but the gas line also? I checked the ground coming from the panel to the water pipe and there isn't voltage present there. Can anyone offer any advise? :eek:
 
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Welcome to our forum.Start by bonding gas and water lines to the ground with at least a #8.Assuming home is very old perhaps you have no ground.Add one to atleast the panel and drive a rod.If this causes a breaker to trip then run it down

[ October 10, 2005, 07:40 PM: Message edited by: jimwalker ]
 
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The water pipes are still live? So I check the rest of this huge house and every faucet in the place is live?
Click to expand...
I would start with the service and check the neutral/ground bonding to make sure that's it's present. From there I would check to see that the hot and cold interior piping systems are bonded back to the service too. It would seem very odd that the water systems which should be bonded to the service neutral can have a voltage on them.
 
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There is a great possibility of a failed water heater element or well. Make sure the bonding is correct. I bet if you bring the bonding up correctly the short will reveal itself.
 
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Think I would go find the "short" (hot conductor contacting metallic something) first.

You shold be able to use VOM to check resistance from heaters and the control switches (depending on design) to the water (tank).

Just a crazy idea -
could the main panel ground system have high
resistance to ground --Has water district replaces the old old steel water pipe with plastic??
AND the sewer system have a low resistance to ground
THUS there is potential between water pipes and sewer.

SOLUTION ?? check resistance to ground from teh main panel check connections and upgrade the grounding system to two stakes.

Most interesting - please tell us what you find.

Dan Bentler
 
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There are several ways to check for this problem.

I agree with find the short first; see if it is just one circuit, or if one circuit shuts off some shorts. Whatever else happens, this has to be fixed.

That there was potential between the tub controls and the drain means that at some remodel in the past, the drain was probably seperated from other drains (otherwise kitchen sink could not be hot, or would have same problem if controls not on sink).

There might be a multiplicity of these problems, not just one with the problem being fed dually, where shutting off one circuit at a time does not find the short.

paul
 
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I had the same call several years ago.
I traced it down to a refrigerator that was plugged into an ungrounded receptacle. The fridge was pushed up against a gas line that was touching a water line...
The refrigerator had a short in it and was going to ground against the gas line. I stumbled upon it when I moved the fridge out to check the receptacle and saw an arc from behind it.
 
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Here are a couple things that we have encountered along with some already mentioned.

Overhead triplex is rubbed, by tree or other means. Went on a call for voltage on refrigerator, plumbing and stove. Found a tree rub on the power company?s side. They came out and replaced the cable and problem was solved. I saw where the cable was damaged.

Another on was a call for voltage in the pool. To make the long story short the neighbor?s washer machine had a faulty solenoid and induced voltage on the ground without tripping their circuit breaker. It went through the neutral across the street (common pole mounted transformer but could due it with common pad one too) then into the other house and into the pool.

Another one recently was a damaged branch circuit. This is the most common one we encounter. We have found houses settling, rodents chewing cables and armored cable rotting. Just enough to induce a voltage on the neutral but not enough to trip the circuit breaker.

Yet another call was to a day care because the children were getting shocked from the plumbing. They were on their own private primary distribution. There was a bad transformer.

I know these aren?t all the possibilities but hope they may help you.
 
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I agree with Infinity:
"I would start with the service and check the neutral/ground bonding to make sure that's it's present. From there I would check to see that the hot and cold interior piping systems are bonded back to the service too. It would seem very odd that the water systems which should be bonded to the service neutral can have a voltage on them"

correct the "BONDING", and the fault will reveal itself.

Grounding is not the problem here, bonding is.

Faults do not want to go to ground, they want to go back to the source they came from. In this case, the utility transformer outside.
 
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Originally posted by pierre:
Grounding is not the problem here, bonding is.
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I would say judging from the responses to this thread, there are a couple here who would benefit from an explanation of the difference. :)

Jim Walker:
Start by bonding gas and water lines to the ground with at least a #8.Assuming home is very old perhaps you have no ground.Add one to atleast the panel and drive a rod. If this causes a breaker to trip then run it down
Click to expand...
Dan Bentler:
Just a crazy idea - could the main panel ground system have high resistance to ground --Has water district replaces the old old steel water pipe with plastic?? AND the sewer system have a low resistance to ground THUS there is potential between water pipes and sewer.

SOLUTION ?? check resistance to ground from teh main panel check connections and upgrade the grounding system to two stakes.
Click to expand...
These solutions do nothing to stop objectionable current over metallic objects in a structure.

It's akin to trying to stop a car doing sixty by opening the door and sticking your foot out. You might slow down a touch, but in general, your shoe starts smoking and the car is still doing 59. :)

Bonding the neutral to the "equipment grounding conductors" (if there are any in this old structure) at the service, and bonding all the metallic piping to that point on the service, should cause a breaker to trip, and from there you can proceed.

Edit wrong link

[ October 16, 2005, 09:41 AM: Message edited by: georgestolz ]
 
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i just did one of these service call last week,my problem was a nuetral splice in a cieling,,gotta do this stuff "T&M'
take your time,you'll find it,
 
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I had this exact situation on a service call a few years ago. Water heater element had shorted to case. Service had been changed several years before and the bond to the waterline had not been installed. 120 volts on all the faucets in the house!
 
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