Voltage in the Pool

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
Hi All -- longtime (relatively) lurker, first-time poster. I've found a few links discussing this topic, but I haven't found (or I missed it) info on how to address this problem. I'll start with a quick dot-dash of my experience, pool and situation:
  • This my first pool and I'm not an electrician (far from it, I've just recently learned to how to use a multi-meter)
  • I purchased this home with an 18,000 gallon in-ground pool (roman style shape) that is surrounded by concrete decking/patio
  • I live in a small town in Louisiana which does not require inspections and has only recently adopted/required building codes
  • The pool (according to the pool guy I have who put in the liner and installs pools for a living) is not bonded. There appears to be no ground wire from the pool infrastructure (i.e., concrete decking/patio and/or aluminium frame) to the grounding pole that is used to ground the pool filter equipment
  • The pool has a vinyl liner (which I recently had replaced) that appears to be attached to an aluminum type frame
  • It is a salt water pool, and it contains a single non-LED light fixture, fountain and some kind of steps to enter the pool (plastic/concrete type stairs?). There are no ladders, there is no heater/heating element
  • There is an in-ground power outlet right next to the pool decking (coming out of the ground) for powering the Dolphin pool cleaner or music or whatever power tools you'd want to landscape around the pool
  • The outlet, pool light and filter are attached to a breaker box (each with it's own breaker) by the pool filtration system and next to the house. Power is coming from the house (wires were run through the exterior wall of the house to the pool filter. This was an add-on to the house and it has it's own breaker box which has a breaker for the aforementioned breaker box that is on the exterior. The internal breaker box in that part of the house is connected to a breaker box in the main part of the house....So 3 breaker boxes that are each connected....this info will become important later
So that's the background, now the situation. I found an experienced pool installer (who also replaces pool liners) who was willing to come out to "the sticks" to replace my faded pool liner, check the equipment and take me to "pool school". He was cautious before he took the job and said that he doesn't enjoy fixing other folks bad work, but that my pool appears to be put in by someone who used to work with his father. So he took the job and replaced the pool liner, the pool light fixture, re-wired the outlet (which was not protected from the elements and had stopped working) and took me to "pool school". My wife went for our first swim and while we were in the pool and both hanging on the side of the pool, we both (at the same time) got a "tingling" shock from the brick trim (and concrete we were touching on the decking/patio. This occurred with our me having turned all the breakers off on the external breaker box....the pool guy had been having trouble with the exterior outlet and pool light, so I felt safer going in the pool by turning all of the breakers off.

As this is getting to (or past TLDR territory) let me bullet out what has been done and checked:
  • Pool guy got an electrician on the phone and he talked him through checking breakers and electrical work. Pool guy brought his teenage son and him kneel on the deck and put his arm in the water with the decking wet and experience the tingling. When the pool breaker was thrown from off to on with the kid doing this, he actually jumped backed from a painful shock.
  • Pool guy was stumped, but after testing everything and installing an anode between the pump and the water going to the pool, the problem was still there. He recommended I get an electrician to check everything out and potentially contact my power company about stray voltage.
  • I got an electrician and after he checked to make sure the breaker wasn't "leaking voltage", we turned off all 3 breakers (the main house, the add on, the one by the pump/filter system) and were still measuring 3 volts in the pool water and at the aluminum strip of the pool frame. He suggested we try sinking three 10 foot copper rods and run copper wire around the pool (which is really around the decking/patio area) to try and "bond" or at least "catch" the stray voltage.
  • I sank the 10 foot copper rods in (with only 6 inches of pole showing), and got 4 gauge (yep, could've used 8 gauge but wanted something REALLY sturdy) and ran the wire in a continuous loop around the pool connecting to the 3 copper rods and connecting the last copper rod to the "known" ground rod over by the pool system. It's 200 feet of wire and as I started to dig the trench (only going in 3 to 4 inches), I thought I should check and see if maybe by some miracle the voltage had magically found my poles and was tossed deeper into the ground. Before sinking the poles, I had used my cheapy Harbor Freight freebie voltmeter/multimeter and got 2 volts in the water. After sinking the rods and wiring them together, but before burying the wire, my measurements showed 6 volts in the pool!
  • I relayed the new larger voltage reading to the electrician who came out, inspected my work, took his measurements with the Fluke multimeter and came up with 6 volts in the pool -- this after the breaker was turned off -- with the breaker on, it read 7 volts.
So the electrician (like the pool guy) is scratching his head and recommending calling the power company about stray voltage....which I'm going to do. But this is not a great power company, my past dealings with them on simple stuff like trees in the power lines have not gone well.

Any thoughts and recommendations would be very much appreciated. I'm sorry this is so long. It's funny, my wife and I bought the house DESPITE the pool, not because of it. But we've enjoyed our brief time in it....and it's hot enough now that the pool water temp is 88 degrees....we'd like to use it, but everybody from the pool guy to the electrician is advising against it. I thought managing the water chemistry, cleaning the skimmer and generally pulling snakes and other things out of the pool was going to be my greatest problem.

Thanks for reading, and for any and all thoughts....

Best regards,
Fred
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
17,357
Tucson, AZ
Absolutely stay out of the pool!!

And it’s rather abhorrent that the pool guy would use a child (yes, even a teenager) to do something as dangerous as a shock test like that. Obviously brain cells are in short supply with that guy 🤬

Read this -


Your pool is NOT properly bonded. Your grounding rods are not the correct fix. Your water, pool structure, deck and equipment need to be on an equipotential bond grid. Otherwise stray voltages can develop.

There is no simple fix here and the areas lack of building codes along with “wildcat” pool builders led to the construction of something dangerous. It needs to be fixed and the fix will not be cheap or convenient.

Do you know if the decking around the pool is concrete? Did they use rebar?
 
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Newdude

Well-known member
Jun 16, 2019
4,566
NY
Was the voltage test done with the whole house shut off, or just that circuit ? During a small remodel of my house I found 2 totally separate circuits sharing a nuetral. In theory if you had something similar you could be bleeding through the nuetral/ground bar of the main breaker instead of the hot leg.

my next guess would be landscape lights, sprinkler pump, defunct power to the shed (I had both landscape lights and shed power run with regular romex by previous owners). or anything else remotely related to the gereral outside area.
 

JamesW

TFP Expert
Mar 2, 2011
21,079
7 volts is huge. Very dangerous. No one should be in the pool until this gets fixed.

7 volts probably means that you have a lot of current flowing through the area.

Get a good True RMS multimeter that can measure frequency and duty cycle and measure the frequency and duty cycle of the voltage.

Also, check the dc voltage and current and AC current.

 
Last edited:

Teaboy

Member
Oct 10, 2017
6
Ipswich, UK
Fred,
I'm not the best guy to answer this - I live in the UK, and our electrical system is slightly different... different names for stuff, and different colour codes for wires - also different wiring practices......
I originally wrote a long and detailed procedure that I'd adopt to get to the bottom of your problem... but I decided to pull it. I know what I would do if the gear was mine... and I've worked with high voltage all my life. But only when I saw my advice on the screen did I realise that I was about to advise you to carry out procedures that could be fatal if misinterpreted. So, I'd get a qualified electrician in. And steer clear of the pool until after s/he's certified your installation as safe.
I agree with NewDude - a "shared neutral" often causes the type of fault, and it can be in a circuit that you would not expect to be associated with your outdoor supply issues.
 

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
Absolutely stay out of the pool!!

And it’s rather abhorrent that the pool guy would use a child (yes, even a teenager) to do something as dangerous as a shock test like that. Obviously brain cells are in short supply with that guy 🤬

Read this -


Your pool is NOT properly bonded. Your grounding rods are not the correct fix. Your water, pool structure, deck and equipment need to be on an equipotential bond grid. Otherwise stray voltages can develop.

There is no simple fix here and the areas lack of building codes along with “wildcat” pool builders led to the construction of something dangerous. It needs to be fixed and the fix will not be cheap or convenient.

Do you know if the decking around the pool is concrete? Did they use rebar?
Thank you for the article and it was horrifying to hear the young man say, "daddy, I don't want to do this anymore". I myself had been foolishly testing after they left by throwing various breakers and testing for "tingling".....which I repeatedly found. Any thoughts as to who I would call to get an established pool bonded? Would it be a pool installer or an electrician? Most of the electrician's involved (2 so far) have been fine when it comes to examining the grounds, checking the load balances on the breaker boxes, but when it comes to the pool, they don't seem anxious to tackle that particular issue....can't say that I blame them.

As to the decking -- it is concrete (pebbled washed stuff that looks to be 3 to 4 inches (maybe more) in depth. I don't know if they used rebar, it appears that it was poured with forms, and some of the forms are large, so I assume so, but I have no way of knowing. I haven't seen any rebar poking out in the ends where I've been digging to bury the 4 gauge wire.

I'm glad you and others have been clear about staying out of the pool. Before really understanding the problem, my wife and I had been swimming in it pretty regularly, just with the breakers off and being careful to not touch the sides of decking/concrete when we were doing it.

I spoke with a pool installer in the nearest city, and he informed me that he's seen this a few times, and it's almost always caused by the power company having a fault somewhere causing stray voltage. Once they fix the problem, then you're fine....of course it could happen again and I'd rather not be near the pool when it does, so bonding seems the smart way to go. I'm just not sure how you bond something that's built....do you have to tear out the concrete and nearly rebuild the pool?
 
Last edited:

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
Was the voltage test done with the whole house shut off, or just that circuit ? During a small remodel of my house I found 2 totally separate circuits sharing a nuetral. In theory if you had something similar you could be bleeding through the nuetral/ground bar of the main breaker instead of the hot leg.

my next guess would be landscape lights, sprinkler pump, defunct power to the shed (I had both landscape lights and shed power run with regular romex by previous owners). or anything else remotely related to the gereral outside area.
Yes...the voltage test (which showed 3 volts on the Fluke Multimeter) was done with the main breaker to the whole house shut off. And after I bury the copper wire, I'll try it measuring again, both with the breaker(s) on and with the full main breaker off. I'm not sure why it went from 3 to 7 volts after the extra grounding poles sunk in. I'm assuming that unless my breaker is bleeding, or the line from the pole to the house (which is underground) has a problem, the shutting off of the main breaker to the house (which kills the power to absolutely everything) should mean that the voltage isn't coming from me (i.e., my house).
 
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JamesW

TFP Expert
Mar 2, 2011
21,079
Does your meter have a frequency setting?

Most likely, you have a significant amount of current flowing through the area.

The more characteristics we can get, the more likely it is that we can figure it out.

Check for DC voltage and measure current on AC and DC.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,862
SW Indiana
The increased voltage with the ground rods would be no surprise to some one who understands stray voltage. The voltage is coming from the soil, so improving the connection will make it worse.

You need a power company engineer and someone from the phone company. Even if you don’t have a phone, their lines can cause this. When you call, be sure to use the words “stray voltage” and “pain”

If you have neighbors close, especially if they have wells, see if you can get them to shut off their main breakers for a minute to test for voltage in your pool.

Don’t try any changes to your pool or equipment until you identify the source of the voltage and correct it. Though bonding would prevent the voltage from affecting anything, you want to fix the problem before you hide it with bonding upgrades.
 

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
Does your meter have a frequency setting?

Most likely, you have a significant amount of current flowing through the area.

The more characteristics we can get, the more likely it is that we can figure it out.

Check for DC voltage and measure current on AC and DC.
I'll try....I'm really bad with a multimeter -- really just using YouTube videos on guidance to use it. My Multimeter is a Cen Tech 7 function meter and appears to measure frequency.....I think.
 

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
The increased voltage with the ground rods would be no surprise to some one who understands stray voltage. The voltage is coming from the soil, so improving the connection will make it worse.

You need a power company engineer and someone from the phone company. Even if you don’t have a phone, their lines can cause this. When you call, be sure to use the words “stray voltage” and “pain”

If you have neighbors close, especially if they have wells, see if you can get them to shut off their main breakers for a minute to test for voltage in your pool.

Don’t try any changes to your pool or equipment until you identify the source of the voltage and correct it. Though bonding would prevent the voltage from affecting anything, you want to fix the problem before you hide it with bonding upgrades.
This makes a lot of sense. I'm hoping the utility companies can/will track this down and I appreciate the "keywords" suggestion when I call. Unfortunately the neighbors are close in proximity, but the water system is not well water. Hard to explain the neighborhood dynamics, but most folks are loathe to turn off their breakers because it messes up their appliance clocks....and I'm the only one with a pool for at least a couple of blocks. Unless the power company is a complete bust, I may well have to go door to door and see if I can enlist some help from them.
 
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markayash

Gold Supporter
Mar 21, 2016
2,587
Atlanta Ga
This makes a lot of sense. I'm hoping the utility companies can/will track this down and I appreciate the "keywords" suggestion when I call. Unfortunately the neighbors are close in proximity, but the water system is not well water. Hard to explain the neighborhood dynamics, but most folks are loathe to turn off their breakers because it messes up their appliance clocks....and I'm the only one with a pool for at least a couple of blocks. Unless the power company is a complete bust, I may well have to go door to door and see if I can enlist some help from them.
I agree, if you tell them you have a dangerous issue and you are concerned they should be there quickly
 
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Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
Does your power feed from the street or the backyard ?
That is a sensible and straightforward question, but my answer will be a bit complicated. My lot size is just over 2 acres, the power pole with the transformer is on the street, the line runs above ground to a pole in my yard, and the electricity goes from that pole into the ground and about 50 feet underground to my house....the pool is another 100 feet away from than that (these are crude measurement estimates, I haven't actually measured those distances. I've had some "progress" since my last post, and I'm getting ready to type that in.
 
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BowserB

Silver Supporter
Jul 29, 2018
363
Katy, Texas
Flintstone, where are you actually, relative to BR. I know you're not in the city. I grew up there, and even in the 1950's there were building codes and inspections galore. A neighbor couldn't put a roof on the garage he built, due to some code--just an example. Anyway where are you?
 

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
First, thank you all for weighing-in and helping me with this. I know it's challenging to help troubleshoot from a distance, and it's even harder when you're dealing with a person with so little base knowledge of the problem. The info (both in links and words) you've all provided has been extremely helpful.

Some changes have happened. As you may recall, upon the advice of an electrician, I sunk in 3 ten foot grounding poles around the pool, ran 4 gauge copper wire connecting those poles and ran the wire back to the "known" ground pole by the pump and that external breaker box. Prior to doing that, I had a measurement of 2 to 3 volts in the water (the 2 different values are from 2 different multimeters, a Cen Tech and a Fluke). After putting in the poles and hooking up the wire (where it was just coiled above ground, so prior to burying it), the readings jumped to 6 to 7 volts using the Fluke -- the 6 volts were if the breaker to the pool equipment was off, the 7 was with it on.

So I started burying the wire (only a few inches deep) and I made sure to lay it in a trench that where it was touching, and in some cases tucked underneath (and touching) the concrete slab which is my "decking" around the pool. It was a difficult job (almost 200 feet of wire), and I finished it yesterday evening. After it was done, I took some readings and here's what I found:
  • All readings done with the Cen Tech Multimeter (since it's what I have)
  • First reading was done with the pool filter/pump running (and I could hear my large air conditioner/fan running): 3 volts
  • Second reading was done with breaker thrown for the pool filter/pump equipment (AC unit still going): 2 volts
  • Wife suggested throwing the breaker to the part of the house with the AC unit going....I did that and measured 0 to 1 volts (the reading would fluctuate between 0 and 1)
Now I'm not really sure what to do. Had I come to you all sooner, I would've not done my pseudo-bonding experiment, and I should've been throwing the breakers and measuring with a voltmeter in a more systematic way to really get a handle on what's what. A few things I know about my house wiring from the electrician....at least one breaker he checked (the pool breaker, has uneven loads....not sure if that's a big problem, he didn't indicate that he thought it was affecting the pool situation). The AC units (I have two large condenser/fan units, one for each part of the house) are not grounded, and he suggested we do that.

I still suspect stray voltage and if I run the "everything", I've got 3 volts in the pool....probably 3 volts too many, I'm sure. There probably is stray voltage in the ground, but my playing with copper has muted that. I'm trying to figure out next steps, which I'd love to get feedback on...here's what I'm thinking:
  • Call the power company as planned and see if they can identify stray voltage using their equipment, which I hope is more than just a multimeter
  • Get an electrician to thoroughly go through all of the breaker boxes I have, balance the loads, make sure there are no shared neutrals, and ground any large external appliances (i.e., the AC units)
  • Try to find a pool contractor/pool electrician who can tell me what would need to be done and quote a price to get the pool to be equipotentially bonded
In the meantime, I'm wondering if the pool is safe with the breakers thrown for the AC Units and Pool equipment, and the measurement fluctuating between 0 and 1. Again, any thoughts on this would be helpful. And has anyone known someone or had their own pool equipotentially bonded after it was installed?
 

Flintstone55

Member
Mar 18, 2020
24
Baton Rouge, Louisiana
Flintstone, where are you actually, relative to BR. I know you're not in the city. I grew up there, and even in the 1950's there were building codes and inspections galore. A neighbor couldn't put a roof on the garage he built, due to some code--just an example. Anyway where are you?
30 miles north of BR -- East Feliciana Parish....town is Clinton. Yep, once you get outside of East Baton Rouge parish, it's a different ball game. Most builders, tradesman and others don't want to make the trip on the two-lane road going north from BR.
 

Newdude

Well-known member
Jun 16, 2019
4,566
NY
if the trouble goes away with the AC breaker off, we can pretty much zero in on the trouble to being on that leg. We can also reasonably assume that this problem is relatively new since the last summer or time the pool was used by the previous owner.

I am going to suspect one of 2 things.

1) the previous homeowner/ electrician mis-wired the AC unit and a hot leg is crossed with the nuetral. This could also be by accident by hitting the power line with a weedwhacker while trimming around the AC units.

the reason that this one ‘jumps’ at me is I replaced the outlet for my oven when replacing it. The labels were wrong on the new outlet box and against my better judgement I wired it up like they said, putting the neutral where the 2nd leg should have been. As soon as I touched the stainless oven, I had that tingle that made me not want to tingle anymore. Not crazy but just enough.

2). The AC unit has a fault and it’s time for service or replacement.