Proper bonding jacuzzi motor to copper plumbing_possible toilet blue stain?

[redikillowatt]

Just a wild hunch here.
Saw several technical posts by engineers, plumbers - about fairly? rare issue of *various* issues between the electrical system & copper plumbing, thought to cause issues from pin hole leaks in copper to possible staining in toilets.

Is bonding a possible cause of following issue I see?

A few technical people mentioned electrical bonding to copper plumbing (or other electrical issues & plumbing) as possibly cause of copper pipe corrosion (pin holes), or toilet bowl staining. The stains are just an indicator.

Only one of 2 toilets (very near each other) sometimes gets "blue stain" in the bowl.
After much thought, only obvious difference in them is, the tub in the bathroom w/ blue stained toilet had a jacuzzi installed a few yrs ago.

The stain or removing it is a small issue. Much bigger - why only one toilet gets it. And if from copper corrosion, what may happen to the plumbing.
National / local code & jacuzzi mfg called for bonding the motor to metal plumbing (if used) within a few ft of motor. It was, using heavy copper wire, between jacuzzi motor & 1/2 copper plumbing, about 6 ft from motor. Using brass electrical pipe clamp on the 1/2 inch copper in wall, near faucet.

Plumbing lines are all in attic. PVC comes from meter up to slab, but don't know where PVC meets copper - in the soil or...? Could dig down, but they don't join above the slab.
The electric service is grounded under the meter w/ 8 ft brass rod (replaced last few yrs).

A blue-gray stain, not blue-green. More soaked into the porcelain, than on the surface (scrubbing products don't do much).
Public water is alkaline, not acidic. (acidic water & copper often said to cause blue or blue-green toilet stains).
Don't use drop in / hang on cleaners.

Any suggestions, comments on electrical issues causing these stains? Steps to rule out problems?
Thanks.

 

[Dennis Alwon]

I doubt the jacuzzi is the issue however electric current on the water lines will cause the copper to corrode and leave toilets and sinks a greenish blue-- or a bluish green-- LOL...

 

[redikillowatt]

Thanks. I guess (peace of mind) could check for current on the bonding wire, or somewhere close to its connection to copper lines?
If electrolysis is the issue, I'd rather check it, than wait for a flood.

Have to admit, with only one main difference between 2 toilets - that also involves electricity, and only one john gets blue stain, it's odd.
Unless someone used "something" in the now-stained john, and forgot. I doubt it appeared overnight (I rarely use this john).

Even found a fair # of posts about certain medication ingredients causing blue toilet stains. A person may not be aware, or stopped the med & now forgot.
All those & more are "possible." One glaring difference between the johns, seems the bonding was worth considering.

I'm no expert, but seems? if the bonding or any electrolysis from current was the cause, the other nearby john might show some stain?
Several factors there. Distance from current source; water flow direction, etc. Copper line length - from stained john to 2nd john, maybe 6 - 8 ft, incl. vertical sections.

Stained john is:
- closest to the bond clamp on copper lines;
- & to water supply (into house) - only place I know *any* metal plumbing touches soil or slab.

Non-stained john is closer to the service ground rod - it's between the jacuzzi bond (on pipe) & the service ground rod.
But from a water flow in pipes direction, the stained john is actually "upstream" from jacuzzi bond clamp on pipe.
The bond clamp & service ground are both downstream (for water flow), of the stained toilet.
Stained john has about 3 - 4 feet copper line between it & bond clamp

May be way off, but I'd assume if there was electrolysis at the bonding point, corrosion from it would flow downstream - to next toilet, not upstream?

 

[cadpoint]

Did you open the water reserve (water closet) to see if the toilet guts are the same?

I'm with Dennis and will assume that current is on the on the grounded pipes.
BTW, I think your opening a big can of worms and this is really beyond your scope of work.

You are only required to do what's required by Code to make sure the equipment is bonded and grounded.

But since your so concerned;
Since your in Texas I'm going to assume that it's a private well, and the owner
is responsible to get their own water tested and treated if it requires treatment.

Water can carry current from water source (well) if the well is also not grounded correctly. In some cases the water can act on the dissimilar metals that it will see on a piped system and due to even very low level current work faster to break the mechanical properties down that it encounters.

They have to draw the water and it has to be tested in 24 hours to understand all that's in a water sample. There's a whole lot more to understanding what's in the water sample, the bigger worry is it's high or low PH level. Multiply sample in this case should be done, draw close to well, draw at toilets and draw from Jacuzzi.
But in the end they need to locate a test facility to assure what they want as a sample!

For your reading pleasure:
Water Resource . net

 

[redikillowatt]

Thanks, cadpoint. If I understood Dennis, he said * IF * current exists on copper lines, it can corrode copper (or other). Not, that current likely existed from the bonding.

One question (maybe a bit down the road, depending) - best practices to check current / voltage, at, near or otherwise, on the copper line near the stained toilet? Even if at the toilet stop valve or other? How much current or voltage we talking, to be a concern for electrolysis?

Thanks for water chemistry link. As said, a big question is, why only one toilet, when so close together? If... the cause is water chemistry, electrolysis on copper lines, etc.
Unless someone completely forgot using a cleaner - couple times - that caused it. The stain "takes a while to develop."
Copper corrosion could be happening somewhere unrelated to the bond. Somewhere upstream from the stained john (based on water flow thru the system).

May be way off, but seems any corrosion at the bonding point, which is downstream from the toilet, wouldn't generally travel against water flow direction in the pipes?

Yeah, thought 1st thing to look inside toilets. Same guts, even same brands fill valves. Down to the style of stop valves & braided flex lines.
Only metal inside both tanks is heads of 2 solid brass* tank-to-bowl bolts. * Appear solid brass - quite old & scratching the heads still shines "brass." Can check w/ magnet.

No, not a private well. A privately owned municipal util. district (MUD).
Again - if it's a source issue, how could it affect only one john?

Another possibility - since stained john is used mostly by one person. Some medication ingredient or other factor, reacting with bowl water. The stain (at least, part that's below water line), is more at front of the bowl. Where urine would run (when sitting). Where the staining occurs below water level, not as much to the sides & almost none at the back of bowl. Down below water line, stain's NOT evenly distributed.
May not even be copper involved in the stain. If it is, may not be copper levels over the legal limit in drinking water.

Water source is deep well water. There's no nearby pump. MUD's pump is many blocks away.
The MUD puts out fairly extensive, state-mandated water analysis every 1 or 2 yrs.