Electricity in my gas pipe?

[Mackey444]

Hi all, 

Thank you in advance for any comments.
I recently found on two occasions that I was getting a very mild electric shock from my shower taps when in the shower. I was trying to trace the issue and found that even with all power off at the fusebox a voltage detector immediately goes off when touching the bathroom taps, and also all the pipework in the loft including the combi boiler. I then went outside and also found a voltage both sides of the gas meter including before the ECV but slightly harder to detect. Power has not cut at any point and all earthing in my property seems ok. 
 

Any ideas what on earth could be causing this? I do have an electrician booked but not for a few days. Some things I read online suggest it could be a neighbour causing it - I wouldn’t put it past one of them to have cut corners. And is it immediately dangerous with regards to gas and the boiler? 

 

[Andy™]

probably a fault outside the property. if its live when your power is off then a call to DNO to investigate would be good

had an almost identical situation a few years ago, downstairs flat getting shocks from the taps / pipework. fault was the upstairs property making adjacent properties live throguh the gas pipe

 

[Mackey444]

Thanks, tried them and they are coming out straight away even though I did explain it was mild! My mistake was starting with the gas emergency line who didn’t want to know! 

 

[Sharpend]

What voltage are you measuring and where from/to? 

 

[ProDave]

My guess failed PEN on the supply cable, gas pipe functioning as the return.  Definitely an emergency "dangerous condition" for the DNO to investigate.

@Mackey444 please come back and tell us what the DNO find when they investigate.

 

[Mackey444]

Mine detector is only a basic one that makes a noise when detected, but comes up very strongly on the bathroom taps and loft pipework, but oddly less so on the gas pipework coming down the wall. 
 

The DNO couldn’t detect anything on his pen but has had to leave me cut off as can’t leave me switched on if reporting shocks and it’s unexplained. So not a happy end to the story ha!  Hopefully the normal electrician can sort it.

He only really checked the area of the meter, I guess anything else is outside of his remit? 

 

[Andy™]

Mine detector is only a basic one that makes a noise when detected, but comes up very strongly on the bathroom taps and loft pipework, but oddly less so on the gas pipework coming down the wall. 
 

The DNO couldn’t detect anything on his pen but has had to leave me cut off as can’t leave me switched on if reporting shocks and it’s unexplained. So not a happy end to the story ha!  Hopefully the normal electrician can sort it.

He only really checked the area of the meter, I guess anything else is outside of his remit? 

DNO are only responsible for the supply into the building. if its still live when your installation is isolated then its nothing to do with your wiring

 

[ProDave]

Okay so get an electrician round.  He can disconnect the gas earth bond and see if there is any voltage or current flowing through it.

What type of property?  Flat, house, terrace, detached etc?

I seem to recall a similar fault some time back which turned out to be an earth rod grazing and penetrating an electrical cable?

 

[Mackey444]

So it’s a end of terrace cluster house, meaning it is back to back with my neighbour then all the rest are normal terrace. Fairly modern mid 70s and most the electric seems fairly modern, this has only recently started. The only other thing still with power in my loft seems to be the old aerial which has a cut off wire, not touching anything. 
 

The only other things I could think of is my neighbour has recently installed a TV arial booster on the outside, plus they had a gas van outside the other day (the opposite cluster house to mine didn’t have central heating so maybe they were getting it installed). He is also constantly banging and hammering doing his own DIY so could be anything. 

Oh and also, virgin recently installed fibre to properties and my tree seems to push my fence and the outside pavement around, if any of those could be culprits. 

Given it was late at night and I am not at my parents, not in a position to ask them anything. 

BG electrician coming tomorrow. 

 

[ProDave]

I am wondering how the gas pipes between the 2 properties connect?  Is anything visible?  is there a visible metal pipe connecting to both gas meters or do they just go underground and not visible?

 

[Mackey444]

So my pipe comes out the meter under decking from my porch then up along the side of the house to the loft where the combi boiler is, it seems to have more detected once in the loft thought, further down it’s harder to get a reading. The other houses are opposite side for their meters, so my front door basically aligns to everyone’s rear doors. 

 

[Sharpend]

Dave is more interested in the pipe that comes into the meter and it’s route.  Is the pipe a metal pipe or plastic? 

 

[ProDave]

Dave is more interested in the pipe that comes into the meter and it’s route.  Is the pipe a metal pipe or plastic? 

Correct.  If it's metal, the fault might be in a neighbours property making the gas pipe live.  If it's plastic coming into the meter then that won't be the case.

Since the DNO have pulled the fuse, you won't get anywhere now until you have had an electrician come and check things and find the issue and tell the DNO the problem is resolved.

 

[Mackey444]

It’s metal coming in so yes could certainly be that. 
 

I’ll let you know what I find out, but thanks for the advice.

 

[Mackey444]

So update to my saga! I am back on which is good! 
 

BG engineer could find no voltage on any of the taps or areas I was detecting it. He said he doesn’t generally trust the wands like I was using for accuracy (made by a company called Intey). Confirmed cross bonding and RCD more than sufficient. 

So that doesn’t solve the issue with my shower shocks but suggests I have had a very unfortunate red herring caused by the detector picking things up when off? So that will require further investigation with the power on. 

I cannot fathom what the detector is picking up, as it works as expected on other live wires. However I noticed that I get a very strong reading all over the felt on the roof of my loft where there is metal sheet gauze like material between my roof and tiles. Could this be related to my detector picking up something very minor from metal surfaces near the tv aerial which has remained live throughout (my

neighbours also on same roof is boosted too)? 

 

[kerching]

Wands/voltsticks are , at best, in the hands of a professional 'handy': at worst, in the hands of an amateur, can be literally 'lethal'. For decades the NICEIC considered them as "tea stirrers"! HOWEVER they are now considered essential by them for polarity checking a TNCS service....go figure

I use one frequently BUT would never trust my life to one.....I can get them to light up by touching earthed metal with them and pawing the carpet with my hoof, similar to a bull

just advising

 

[Andy™]

HOWEVER they are now considered essential by them for polarity checking a TNCS service....go figure

if only there was something like a proper earth that could be used as an extra reference point to verify polarity

 

[Doc Hudson]

So update to my saga! I am back on which is good! 
 

BG engineer could find no voltage on any of the taps or areas I was detecting it. He said he doesn’t generally trust the wands like I was using for accuracy (made by a company called Intey). Confirmed cross bonding and RCD more than sufficient. 

So that doesn’t solve the issue with my shower shocks but suggests I have had a very unfortunate red herring caused by the detector picking things up when off? So that will require further investigation with the power on. 

I cannot fathom what the detector is picking up, as it works as expected on other live wires. However I noticed that I get a very strong reading all over the felt on the roof of my loft where there is metal sheet gauze like material between my roof and tiles. Could this be related to my detector picking up something very minor from metal surfaces near the tv aerial which has remained live throughout (my

neighbours also on same roof is boosted too)? 

Without using an approved test meter, that can show an actual measured voltage, with two test probes, one connected to a know 0v Earth point and the other on the suspect live item, any testing is not much more than random guesswork that may or may not prove anything.  If you don't have access to a proper test meter you are probably better using a traditional Neon-Screwdriver on the pipes and see if that glows, rather than a non-contact voltage detector pen/wand.

Doc H.

 

[UNG]

 HOWEVER they are now considered essential by them for polarity checking a TNCS service....go figure

I prefer one of these https://www.socketandsee.co.uk/socket-and-see-epf-pro-hazardous-voltage-and-phase-finder.html

 

[poni]

I prefer one of these https://www.socketandsee.co.uk/socket-and-see-epf-pro-hazardous-voltage-and-phase-finder.html

what do use that for?

I hope that its not for proving dead! as you could end up being the proving unit and dead!