Problem with voltage on kitchen sink

[kwired]

190921-1146 EDT

EIPuma07:

This morning with whatever loading I may have I read 0.2 mV from one end of the main panel neutral to the other end. Half way along the bar it is 0.1 mV. From neutral bus to EGC bus about 0.5 mV. Frome neutral bus to water meter 1.5 mV.

Next to kitchen.

At an outlet within 1 foot of the sink I read 197 mV neutral to its EGC. Same outlet EGC to disposal ring 30 to 50 mV varying. Same EGC to sink faucet 8.5 mV quite steady. Sink tub to disposal ring 0.0 mV.

With breakers to both the dishwasher and disposal off the faucet to sink is a steady 26 mV. Same when dishwasher breaker is on. But when just the disposal breaker is on there is the fluctuating low to 50 mV variation. The switch to the disposal has an internal neon bulb that is 53 years old and does not remain on steady when the switch is off. I am surprised that the small neon current, possibly 120/100,000 = 1 mA would cause that much voltage variation between sink and faucet. Also seems to imply that faucet to sink is somewhat insulated. That I don't expect. If I unplugged the disposal I would expect the same as the breaker being off.

These are just some measurements for you to use for comparision.

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Your measurements are all in mV ranges, OP said he had at or near 120 volts between supply line and I believe the drain line. Which one is at/near ground and which one is energized is the next thing to investigate here.

 

[gar]

190921-1305 EDT

kwired:

Yes he has said 120 V and that is is huge relative to what it should be. Should not be hard to find it.

First, we need to know if everything is good at the main panel.

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[ElPuma07]

Thank you everyone its hard to get to each response just yet. I will be heading over to the home in the coming days to start troubleshooting. I imagine this happened when the kitchen was remodeled and flipped. They old owners also converted their garage into a spare room and its run off the kitchen circuits as well so I imagine I'll be running some new home runs regardless.

 

[brantmacga]

Last time I saw this, someone had disconnected the water line bond when replacing the water heater.


Sent from my iPhone using Tapatalk

 

[ggunn]

In a rent house I lived in for a while there was an aluminum framed window in the shower. I learned very quickly not to touch the window frame when I was standing ankle deep in water.

 

[ptonsparky]

A customer had cast iron drain lines in their house that were at a slightly elevated voltage. Enough so that touching the tub faucet while she was in it caused a shock. Turning all the power off to the house did not remove the voltage. We ended up bonding a short section of smaller galvanized drain line to the GES to solve the immediate problem.

We see enough cast iron and copper waste lines that we bond them.

The point being the fault could be to the drain, not the faucet.

 

[ElPuma07]

Ok so an update! I started tracing out all the lines and he’ll they put way too much on one breaker fridge/counters/microwave etc etc so I’m gonna re feed some stuff with new circuits. Started taking apart the outlets and found some jumpers from the neutral to the grounds. Figure this was their way around having open grounds on everything (it’s an old house) so finally I redo some GFIs and such and go to heat everything up.
Everything turns on fine no shocks while touching the sink and water at the same time. So I think well I better check the water lines below as before if the water line feeding the dish washer swung and hit the actual valve for the other water line it would arc.

No voltage from dish washer hot water to cold water valve. Plug in dish washer and there it is. 120v from water line to dish washer and valve on the cold water. I’m thinking some mice (which has been an issue) have chewed up the dish washer and now it’s throwing voltage through it’s water lines.


I disconnected from that circuit and ran the dishwasher through another circuit and the voltage returned.

 

[oldsparky52]

So you have a dishwasher problem?

 

[romex jockey]

Ok so an update! I started tracing out all the lines and he’ll they put way too much on one breaker fridge/counters/microwave etc etc so I’m gonna re feed some stuff with new circuits. Started taking apart the outlets and found some jumpers from the neutral to the grounds. .

The switch to the disposal has an internal neon bulb that is 53 years old and does not remain on steady when the switch is off

hmmm.....:angel: ~RJ~

 

[gar]

150929-0802 EDT

romex jockey:

In times past when LEDs were not so common lighted switches tended to use a neon bulb for long life. This bulb would light when the switch was off and power was present. The neon bulb and its series resistor were in parallel with the switch.

The neon bulb electrode emissivity deteriorates with time of current flow and requires a higher breakdown voltage with age.

With LEDs there is also an aging process.

In an AC circuit an LED will require another LED in parallel and of opposite polarity to prevent excessive reverse voltage, or a shunt diode for that purpose, or a series diode with a high enough reverse breakdown voltage (PIV) to prevent exceeding the LED PIV which is very low compared to 200 V.

.

 

[hbiss]

So you have a dishwasher problem?

He has a dishwasher and a plumbing bonding problem. The faulty dishwasher should have caused its branch circuit breaker to trip if the hot and cold were properly bonded at the service entrance. So don't think this is over by replacing the dishwasher!!

-Hal

 

[Little Bill]

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