Bad JuJu ?

JCL

Looking for some advice. I posted a while back about some Navien issues, and really found nothing water related at that time.

Now, I have 2-AO Smith HYB90's in place of the Navien's. The Naviens of the past leaked after 1-year through the heat exchangers. We went through the water and nothing stood out. To this day Navien has never produced a water quality list of do's and dont's. So, now what is my problem? Well the anode rod's on the HYB's turned turquoise blue started breaking off and plugging the filters on the Hybrids on a weekly some times daily basis after 1-year of install. Upon another plumbers recommendation I put a ground wire from the gasline to the Hot & Cold nipples on the tank's.

I did find that the voltage between the neutral and ground measured .395 volts. And the voltage between the neutral and gasline was the same .395 volts.

This is new construction 3-yr old with PEX, gas line is tied into the neutral and ground via bonding wire, while I was there last I made sure the bond wire went into the earth.

Any Ideas? Is the .395 volts excessive or a non-issue? Ever heard of something similar happening?  I am turning to the experts now, that is you.

Looking for advice.

Thanks,JCL

Jamie Hall

Interesting...

0.395 volts is enough to cause some interesting electrolytic effects... and shouldn't be there.  Neutral and ground should be at exactly the same potential, or with at best a very small -- millivolt range -- difference.  So anything solidly tied to either one should also have the same no or very small difference.  The fact that your neutral and ground are at a different potential suggests that somewhere you have either a bad or loose connection -- or none at all -- or that something is leaking a voltage into one or the other (more likely the neutral).  Sadly, the problem can be a bear to track down, and doesn't absolutely have to be in your own house -- anywhere from the utility transformer in can cause it.



This is a job for a good electrician; while not an emergency, it's also not something you want to leave for some other time...

Jack

Trying to find these

electrical gremlins can be an invitation to your own personal twilight zone. As Jamie pointed out, it can go all the way out to the service. When i bought my home in MA many years ago, I could not keep my equipment running reliably. As well, I was popping light bulbs like crazy and I blew a vcr (remember them?). I of course kept my head in the equipment, and the problem was found by the carpenter. I had the place re-sided in the spring and the carpenter doing the work dropped his hammer and broke the jug off the electrical meter. The utility guy came right up and called me over to show me that the neutral lug on the house side of the meter was totally corroded. Upgraded the service a bit sooner than I had planned and all was well for the next 17 yrs. Ask the customer if they are seeing any other electrical anomolies. Thanks for the update. Keep us posted, and good luck.

Zman

Wow

I think there is some basic stuff a non electrician can do. You could certainly inspect the neutral bar in the panel for loose wires and corrosion.(turn the power off and don't put your tongue on  the mains) The ground from the panel to the earth and panel to the water service would be a couple others to look at. Have you tried turning the main breaker off and seeing if the voltage changes? You could also turn the breakers off one by one to see if the problem is from an individual circuit. Sometimes you can locate the source by just looking around the house for "non electrician" workmanship.

It is amazing to me how much corrosion occurs as a result of very slight currents. The corrosion of  huge rebar grids in structures has been attributed to this.

Please let us know how it goes.

Carl

BobC

Many moons ago

I was talking to my aunt in the next town and she mentioned losing light bulbs and having some dim a lot when the refrigerator came on. When i went over to check i found the ground lug in the old panel (1950?) corroded to hell. I pulled the main fuses, cleaned everything up and everything was a lot happier.



The connections in panels can loosen up over time because copper can and does flow, after the 2nd or third round of tightening things are usually all set. If you attempt to do this yourself make sure you turn off the main and have someone standing by to pull your smoking remains off the panel.



Bob

Jean-David Beyer

copper can and does flow

Nowhere near as fast as aluminum, though.



Where I used to work, the main power feed cables were aluminum. Building designed in about middle 1950s. It came inside the building to the various 200 amp power panels on each hall on each floor. Copper from the power panels to the loads. About every 6 months a guy from the plant department measured the temperatures of the connections to the bus bars with an IR thermometer and they tightened the bolts of the ones that were too hot. I do not know what they did if they crushed the metal out altogether. If they had enough spare cable, they could cut the end off and start over, but at some point it would get too short. It lasted 40 years for sure.



https://upload.wikimedia.org/wikipedia/commons/0/08/Holmdel-cropped.jpg

Steamhead

Talk about a "crystal palace"!

must be some money there, I see a Porsche 911 in the parking lot! What company is it?



And I hope those weren't Federal Pacific panels............

Jean-David Beyer

must be some money there

There was. That was built by AT&T when they were a regulated monopoly. Since they were broken up by the justice department, they fell apart and no longer exist. That building was taken over by a spin-off of AT&T known as Lucent. And Lucent fell on hard times and was taken over by Alcatel, that is not doing all that well either. That building has been abandoned for several years now. We had about 8000 employees there when I worked for them.



It is Bell Telephone Laboratories, in Holmdel, New Jersey. It was designed by Eero Saarinena famous architect.



https://en.wikipedia.org/wiki/Eero_Saarinen



I do not know who made the power panels, but since we did not get fires in the electrical system, I doubt they were Federal Pacific.



The building had an interesting HVAC system. Hot and cold air were circulated in ducts throughout the building. Each room had a mixing box controlled by a pneumatic thermostat. It mixed hot and cold air as needed to satisfy the thermostat. I cannot believe they used hot air furnaces, because the building was too big. They had steam boilers. So there were probably heat exchangers located to heat the air locally. Also, to prevent the outside windows from getting steamed up in winter, they had steam baseboard heaters along the outside windows. In an economy move, they turned those heaters off and the windows did all steam up. Made a mess.



In the computer rooms they had to have humidifiers to control the humidity. I am talking about one room with three IBM 360/65s and a 360/50. The humidifier has a steam pipe coming in, and a clever valve that mixes the steam with the air and blows it into the room.



They had another cooling system too. They piped cold water (about 40F) throughout the building, and where cooling in excess of the cold air supply was needed, you could tap off the cold water, run it through a heat exchanger, and back into the cold water line. Chillers were in the boiler room, and the heat sink for the chillers were two large pools outside the building.When the pools got too hot, pumps sprayed the water into the air resulting in evaporatative cooling.

nicholas bonham-carter

Ju-ju shower

Twenty five years ago, tennants in our apartment house were having bad luck with microwave longevity, sometimes only lasting a few months. Then they told me they felt electric shocks while showering, and then moved out to other jobs out of town.

When we upgraded the house wiring to breaker panels (non-federal pacific), we found the old screw-in fuses were corroded on the neutral side, but not the hot, explaining the shocking shower!--NBC

icesailor

Bad Neutrals:

I can't stress this enough. Ignore at the peril of your potential life.

If you see lights flickering in some places in your house and not in others, or you see some lights in a room becoming so bright that it hurts to look at them and others are so dim you can see the filaments, If you hear electric motors speeding up and slowing down, if you feel small "jolts" or "tingling" when touching faucets or other electrically connected objects, DO NOT FRIGG AROUND, EVER!!!!! Don't pick up the phone, don't operate light switches, don't do anything but LEAVE and go to a neighbors house to call the power company and tell than that you think that you have a problem with your neutral and tell them what you are experiencing. They will be there so fast, you will think that you have called the Fire Department. Faster than the gas company.

Imagine a generating facility. Imagine all those wires coming out of that plant. There are four of them. Three hot wires and one neutral. Imagine everything leaving the plant as little "V's". Imagine that every one of those little "V's" has to go back to the plant to make the circuit. If something happens to the path back, those "V's" must find a path back home. Should you get in the path, it could be a fateful experience.

Don't always expect to find an electrician to locate the problem. I have seen "shocking" experiences when people were using an outside shower and I could get 14 volts to ground. The power company's answer was to put rubber garden hoses on the handles. When the actual problem was an unbalanced load in their 3 phase primary circuit where the primaries were trying to balance themselves through the earth. Last Summer, I had a no hot water service call on an electric hot water heater. The power company had to put some device on the transformer to stop stray voltage from a primary in the ground from getting into the transformer and powering up the neutral.

Those situations described here with the corroded neutral bars are deadly.

And I won't even go to what happens to electronic controls with voltage in the neutrals.  

icesailor

.395 volts: Just a tickle:

You need to have your water professionally analyzed. One thing to check is the PH and Conductivity. PH below 7.0 is acidic. Certain dissolved solids will make the water more conductive to charged atoms having a party and your plumbing is their gift to each other.

You need a comprehensive water test. Not the short form and not the longest one. There should be a water testing lab near you. A good test used to be around $100.00 the last time I did one. Water treatment companies do testing but they may give results more geared toward selling water treatment equipment. Usually, your local health department sends samples to labs. I would ask them about it. Sometimes, they will send your sample along with theirs for a fee.

 

Larry Weingarten

thoughts

In the original post there are three things I'll comment on.  First the anodes. They sound like aluminum.  Change to magnesium to get rid of the excessive corrosion byproduct.  Next, the stuff is getting to and clogging the faucets.  Is there a recirc line that doesn't have a working check valve?   Third, you say the bonding wire goes to earth.  Does it all tie into a single grounding rod connected to the main panel?  With multiple grounds, you can get resistance in/through the earth giving you grief.



I agree with icesailor about bad neutrals.  They are tricky AND dangerous.  I've looked into an old style meter box made of aluminum, to find steel screws and copper wire, all wet from a leaky weather-head for years.  Verrrry messy!



Yours,  Larry

icesailor

Annodes

I have never seen an aluminum annode rod. Every one I have ever seen was magnesium.

ChrisJ

difference between ground and neutral

As a homeowener I have to ask,  if you are drawing some current, say 10-15A on a 120V 20A circuit, wouldnt you expect to see a voltage difference between neutral and ground at the appliance?  Perhaps more than a volt or 2 depending on the length of the run?



You would have to be dropping some voltage across the neutral due to the current flow through the circuit, but would not have any drop on the ground ergo a difference between neutral and ground yet nothing would be at fault.

BobC

#12 is 0.0016 ohms per foot

Lets leave any effects from line inductance and capacitance out of things for now. A #12 wire is about 0.0016 ohms per foot, at 20a that would be 0.032v per foot. That means there could be 3.2v drop (0.032v X 100ft) on a 100 ft run of #12 wire but most runs in a house are not 100 ft long.



Nothing you can touch outside of the electric panel should allow you to contact the neutral wire, you should only be able to contact the ground if the appliance has a grounded cord.



Bob

Mark Eatherton

Simple test....

Turn the main power disconnect to the house OFF, and see if the voltage potential is still there.



It is possible that if your neighbor has lost their neutral, and the Earth ground is acting as the only ground (thinking grounding clamp on the cold water line in a municipal setting) and is back feeding electricity to your home.



I've been shocked cutting a 3/4" copper water service clear out by the street before. Not an experience I'd care to do again...



ME

archibald tuttle

Bingo - not JuJu but NEV (Neutral to Earth Voltage)

Chris, you hit it on the head, although with a boiler likely located close to the electric service you will not have much potential between ground and neutral via internal line loss/load.  even .3 or 4 sounds high for the loads involved, and, in any event you wouldn't see any when you weren't using the applicance if the voltage drop related to its own electric consumption were the issue.



rather you have stumbled in an area that I stumbled into a few months ago when our horses wouldn't drink out of their water trough, dutifully protected with a GFI that I thought would be the first indicator of anything electrically amiss.  Now I have had my experience with bad local neutrals although this creates just the type of indications that other posters are talking about because in any 240 V installation, if the neutral is bad then one leg goes high on voltage and the other low to balance depending on the loads on each leg.



I actually had an outbuilding a few years back where we lost the neutral and could not find the problem (800 foot line through trees) and were' trying to keep the lights on and wrap up an event and so we turned loads on and off monitoring the brightness of two light bulbs that were on opposite legs of the 240 and once we got them about even we just a stopped and changed nothing on the electric and just stopped using all appliances and water and what not, had some lights on and everything was beautiful.



But the kind of problem you describe is just as likely related to the voltage drop on the utility company side -  if you've got somebody calculating that you could create a 3 V drop or differential between neutral and ground 100 ft. out with a 20 amp load on 12/2, what do you suppose the electric company could have on several or more miles of cable running back to the substation. And what happens when lines that bore this in mind when they were run are loaded with service to new customers in areas that didn't anticipate significant build out or significant increase in loads for the existing build out.



Voila, you have the problem sometimes labeled stray voltage although this label can loosely include minor nuisance voltages of the sort reported here and full voltage exposed on various surfaces -- the kind that electrocutes dogs walking on manhole covers occasionally.



As you can see if you want to watch the technical explanation (very good explanation and as soon as I saw it, it was dawn breaks http://www.mikeholt.com/strayVoltageVideo.php ), there are transformers that don't bring that voltage drop across from the primary to the secondary but the type of transformers common in the united state do.



This phenonmenon has been a very serious problem for dairy farms (think milking machines . . .  how'd you like to have 4 or 5 volts hooked up to your udder). All of that said I don't really look at it as the utility's problem. And at fractions of a volt it is definitely about how to safely isolate or protect appliances with sacrificial electrodes. They can't possibly invest in replacing all these transformers or stringing new lines albeit the system we have built up does exhibit some problems.  The biggest problem is that rural electrification -- i.e. that with the longest runs for the least customers -- was brought about by artificial political interference and our service in rural areas is priced identically to urban service.  that is ridiculous. I'm not asking for higher rates or to get on or off the grid, but it is just stupid and this modest problem is delivered to us as an unintended consequence of meddling in markets for electricity. Unfortunately, when it bothers enough people it will no doubt be the subject of more not less meddling.



My problem (long story here if you care -- http://www.electriciantalk.com/f2/small-current-leakage-livestock-trough-heater-32802/ ) varied between 4 and 7 volts and although the horses alerted us to the problem I realize I had experienced it myself.  When I'm using a diamond blade on a saw or angle grinder and I would plug into a gorund fault (that I had just tested) and spray a little water to keep  the dust down and then my knee would touch the ground and I'd get a little sizzle.  And I could never figure out why that didn't trip the ground fault. It was always minor and not like grabbing 120 even but you could feel it.



Well, of course the current is the potential left due to the voltage loss in the netural return, and it does not create a differing amperage on the two legs of the Ground Fault which is what causes them to trip.



While a bunch of ground rods can help, they can actually hurt when it may be, as someone mentioned, a significant loss of neutral in the neighborhood somewhere that actually feeds in reverse  through the ground rods and back to the neutral on other boards.



The main insight that I gained from hours -- or maybe days - researching this NEV - Netural to Earth Voltage - is that potential takes all pathes to ground proportional to resistance.



So here I am mystified as to how the ground rod to the earth can show a potential because the ground rod is pounded into the earth.  But the potential is still there and if you are another path - e.g. through the angle grinder, my body and wet knee, or through the horse standing on the ground and drinking from the trough with a grounded water heater in it, or just another ground rod, it will take that path too.  It doesn't take one in preference to another but the divides the current based on resistance of the varying paths.



Of course I knew this in theory, but a couple of shocks helps you know it in practice.



Ironically, what we did for our horse problem was to unground the heater (at least the ground bonded to the neutral back at the panel that is) - the actual transmission of the NEV to the water was through the grounding prong and we grounded the tank water with copper wire looped through the bottom of the tank to its own grounding rod.  And then we test the GFI daily. Although my experience has been with more GFIs failing off, apparently the dominant failure mode is actually for them to fail on (found a great report on testing failed GFIs to suss this out, haven't got the link around at the moment but rattle your sabres if you're interested), so frequent testing to make sure if the heater melted down and the real voltage got loose in there that there was a protection.  Not a particularly likely scenario, but would be the high voltage version of stray voltage if it ever happened.



After all that reportage, of course, I am suddenly interested in what various boiler manufacturers and heating professionals familiar with this phenomenon recommend regarding re grounding and annodes, cathodes etc. This may, in fact, be the principal driver of the use of sacrificial devices in the first place, I'm unsure, but I hope to get surer after riding this thread for a while.



Everything I have in operation right now is cast iron and although I imagine that is theoretically sacrificial in comparison to the rest of the installation in copper and brass, it also tends to thicker and I guess has proven resilient in practice. So I'm not losing sleep but eventually I'll be looking to install modcons once I finish radiant installs and abandon the steam system, so I'll be watching this thread, if anyone happened to get through my post and see that there was a question after all the pontification.



brian

Mark Eatherton

Wow, udderly shocking....

No horsing around here. Adds new meaning to "stimulating milk production". ;-)



Shocking.



Thanks for sharing brian. Good stuff there. I too wonder what the net effect is on metal deposition/removal.



ME

icesailor

Fused Neutral?

That building must have been older than dirt. Its been illegal to fuse neutrals for longer than I know about. For that reason. In really old cribs where they had cartridge fuses on the main, if it had a third fuse, or it was a 110 volt service and they connected the neutral to the other fuse, the fuse could blow and you wouldn't know it. Should you be in the way of voltage looking for a path home, you could become excited.

icesailor

Electric Animals:

I once knew someone who used a child to check if their electric fence was working. Child Abuse.

You must have had a stock tank heater in your water tub, Many horses will not drink really cold water and get colic. We have a TB who will absolutely not take a sip of water that is under 45 degrees. So he gets heated water all winter. If it isn't heated, he will colic within 3 days. He will only eat his feed mixed with hot water, like a porridge. Then, he takes a mouthful of hay and runs it around the feed bucket to get all the gravy. When done, the bucket is shining. We once had a horse that would start colicing when it got cold. We figured out that he had sensitive teeth and the cold water hurt his teeth. We gave him warm water and that ended it.

I've seen a lot of stock heaters that bleed electricity and not trip a GFI. You know that there is a problem when horses are standing around the tub with a quizzical look and not drinking.

When it comes to electric livestock fences, I buy the biggest ones you can get. I will use a charger rated for 50 miles of fence for a 100' X 100' enclosure. The grounding is the key. I drive up to 5 ground rods, 5' apart, connected with #8 wire connecting them together and to the ground connection on the charger. I have a fence tester that has 5 lights. I'll get 5 lights close to the charger, But as far away as I can get, and I may only get 3 or 4 lights. But as I move around, the amount of lights will change. There are better electrical paths locally. The animal becomes the connection and completes the circuit. I've seen horses go down on their knees to reach under the wire to get a nibble under and outside the wire. They know absolutely where the wire is.

Then, there's moving a fence wire and the horses won't cross the line of where the old fence was, Until some brave soul does. Then, they JUMP over the spot.

They're not fools.

nicholas bonham-carter

Older than dirt?

The house was built in 1885 by my great-grandfather, and then remodeled/enlarged into apartments by my grandfather in 1920. My wife and I have been working on this house since 1970. When we started, we made a list of things to be done as there was a lot of deferred maintenance (!!!!!). I thought when we started, that when we finish the list, we will be done, as you know things keep on jumping up onto the list, just as you finish a previous item!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!-NBC

Plumdog_2

Not fools is correct

After having two flocks of chickens eaten by The Bear, I strung two strands of electric wire around the coop, and used a large-size Pet Fence Electrifier given to me by a guy that had Dobermans. Been about 3 years and no more Bear Trouble. So I built a second coop and strung the same kind of wire with the same kind of bright yellow insulators, but never hooked it up. The Bear leaves that one alone, too. But I think a new crop of Bears is coming soon.

archibald tuttle

lions, tigers and bears

the worst i used to run into was possums eating the eggs, and they didn't care about electric fences too much.  Have to get chicken wire were every other strand is nylon so that alternation strands could be connected to opposite polls of the fence charger and then you'd be somewhere I guess.



meanwhile here: http://www.mikeholt.com/documents/freestuff/NEMA-GFCI-Field-Test-Survey-Report-January-2001.pdf  is the GFCI report I was talking about.  fair amount of dry reading, and the appendix of raw data doesn't have a good explanation of terms but I believe if you look under the "Test Results" column that "Off" means it functioned correctly when you hit the test button and "Trip/On" means that the test button actually did physically release the solenoid but the power didn't go off (I think due to self welded terminals is the principal cause) and "No Trip" means the power didn't go off and "No Reset" means the GFCI would not energize.



Somewhere there is a graph detailing the percentage of various failures, but I couldn't find it in a hurry, but just scanning the raw data shows you a lot more Trip/On and No Trip failures than No Reset failures.



As I said, I've personally experienced more No Reset failures myself, but this was a fairly randomized approach where they just had electricians who went out on jobs testing previously installed GFCIs for a statistical field inquiry so I tend to trust these resutls more than my own experience.



And although I had never seen a GFCI that failed to trip when I read this study, I did find one the following week. not exactly Q.E.D. but. . .



The other thing I didn't mention that has been used on dairy farms is loosely called a "tingle isolater" revealing its roots in candadian farming - if it were a product originally aimed at american farmers it probably would have been called a zap stopper.  got to love that understated use of the language.



As far as I can tell these are still available but they cost over a grand which seems a little excessive. Not bad if it is isolasting a full farm load for a dairy, pretty easy to justify, but for recreational horsekeeping of a few four footers that is kind of a tall order.  I'm debating manufacturing an igloo for the water tank so maybe it doesn't need heating.



But if someone were to make a much lower amperage tingle isolater as a much lower amperage price maybe it would be additinally effective for boiler control circuits where electric or electrically controlled appliances in constant contact with water -- pretty much a ground by definition at some point along the way.



I'll get on it right after i perfect my better mousetrap.  (and better thermostat -- all the features of an invensys 9700i with information communication and logging capability maybe 4 channels and state polling and multiple switching and wifi to send all the info and take instructions from the computer. )



Brian



 

Mark Eatherton

Bears...

At my mountain home, we had an issue with a bear that decided to take our 55 gallon drum (locked) dancing down the hill. I took a dog shocker and set it up as follows;



4 X 4 plywood sheet as the base.



2 X 4 blocks strategically placed on top of the plywood to support the 55 gallon drum.



6 X 6 welded wire mesh paid on top of the plywood with the 2 X 4 blocks protruding through to allow the barrel to sit on top of the wire without touching it.



Ground rod driven into the ground. Ground wire connected to the 6 X 6 WWM. Hoot wire connected to the 55 gallon drum.



First night out, the bear made the mistake of walking up to the barrel and touching it. We heard a LOUD noise like a bear screaming bloody murder. Last time we saw THAT bear, and like you, am awaiting a new crop of dumber bears to come along. This time, I set a motion detecting light, and a motion detecting game camera to see if we can capture "the moment of shocking truth".



So far, my "device" has killed off a dozen curious chipmunks trying to climb under the 55 gallon drum. Too many of those little buggers running around anyway. I've nick named one of them Grizmunk. Have yet to catch him tho. He's one of those Alpha chipmunks that isn't even afraid of man or beast, hence the name Grizmunk... Stands about 8" tall, 3" wide.



The whole shocking system is on a timer and is only "enabled" during the night (after 10 PM, off by 6 AM) and all guests are made aware of its function.



Enjoy!



ME

archibald tuttle

geez, I must need glasses

ME



at first blush I thought that said 8 feet.

Mark Eatherton

Now THAT would be a tall tail...

Inches, not feet :-) I'd be trying to trap an 8 footer for the freak show.



ME