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Grounding question

brewchief

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I've got a grounding scenario that I'm not exactly sure how to handle, could use another point of view.

I've got a customer that lives in a 12 year old condo that we just installed the 4th or 5th water heater in, talking to the water heater tech line they said there might be a ground issue in the house that is leading to the early demise of the heaters. Tech line guy recommends a ground wire on both the hot and cold lines at the heater run outside to a new ground rod.

Electrical service is currently grounded to the cold water line and two ground rods outside. Water line is copper from the street and there is a ground clamp on each side of the meter, there is a water softer that breaks the line but it does have a metal clip that is designed to keep a solid connection.

Is grounding the water heater lines separately a bad idea? My thought is to tie the hot and cold lines together then run outside and clamp to both existing ground rods, I could add a third but I don't see the point.

FWIW this is a gas water heater, power vented, all copper piping in the house
 
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wyliesdiesels

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I've got a grounding scenario that I'm not exactly sure how to handle, could use another point of view.

I've got a customer that lives in a 12 year old condo that we just installed the 4th or 5th water heater in, talking to the water heater tech line they said there might be a ground issue in the house that is leading to the early demise of the heaters. Tech line guy recommends a ground wire on both the hot and cold lines at the heater run outside to a new ground rod.

Electrical service is currently grounded to the cold water line and two ground rods outside. Water line is copper from the street and there is a ground clamp on each side of the meter, there is a water softer that breaks the line but it does have a metal clip that is designed to keep a solid connection.

Is grounding the water heater lines separately a bad idea? My thought is to tie the hot and cold lines together then run outside and clamp to both existing ground rods, I could add a third but I don't see the point.

FWIW this is a gas water heater, power vented, all copper piping in the house

This is a weird one. What exactly is dying in the H2o heater? I was about to say it was corroded due to hard water but then I saw the water softener comment. Maybe the water softener isn't functioning?

Many jurisdictions follow the NEC code that requires the bonding of hot, cold and gas piping @ H2o heaters. And some also require an EGC that runs back to the GEC/service!

What I can't seem to figure out is how the absence of water and gas pipe bonding would cause the H2o heater to prematurely fail. Maybe the guy on the tech line doesn't know what he's talking about! The H2o heater in the place I rent does not have bonded pipes and its 12 yrs old. I have seen many, many H2o heaters without bonding and they are older than the ones in your situation.

Something is missing here.... : /
 
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brewchief

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I believe the thought is that the tanks are dying due to electrolysis, water softener is working and water has been tested in the past, the one before this one I also talked to the tech guys and they said to verify that the house was grounded.

It's got me baffled, I've never run across something like this.

I think we will go and bond the hot and cold and I guess might as well hit the gas as well, I was mostly worried about the suggestion to ground it to a separate rod, my spidy sense says this might not be a good idea, I think it should go to the rod(s) that the panel is grounded to.

The heater is connected with dielectric unions, I wonder if I should add a clamp on the heater side of one of those as well?
 

wyliesdiesels

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If you're an electrician, I'm sure u know that all rods need to be tied together. Separate rod is fine as long as its connected to the other rods.

This IS odd! Not sure where to go from here. As I said, there's thousands of heaters that are unbonded and don't fail prematurely!
 

MrMark

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Tech guy is full of it. There should be ZERO current on that ground wire and ground rod system. It is there for lightning mainly, not anything much else. The house would function just fine without it and be just as safe too (except for lightning.)

What is a ground wire going to do? It is already bonded/grounded.

Another ground rod might help if lightning hits it.

If that heater is hot, as in current is flowing through it because the copper in the house is hot, you should be able to figure that out. That is a stay current problem, NOT a ground problem. Grounding the tank another time isn't going to do anything about that stray current. It is already grounded through the cold water bond, which is where stray current, if present, may be coming from.

No one understands grounds, they think they are some magic.

Are you getting shocked at the heater when you disconnect the water line? Any history of shocks at the house from touching the plumbing when wet? Do you have a clamp? Can you clamp the incoming water line to see if it is carrying any current? If it is, that is your problem. Fixing that may require an isolation bushing on the main water line.
 
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pattenp

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I don't think grounding is your problem. Read this....

Water Heaters

The average water heater will last about 12 years according to industry statistics. Sadly, far too many water heaters fail long before that. With a bit of periodic maintenance, a water heater should last well into its teens or longer, thus, saving you money and reducing our nation's landfill sites.

Although there are various styles of water heaters in this country, the most popular is the tank type, which is fueled by natural gas. An electric variation contains one or more electrical elements that heat the water. In either case, a water heater will operate more efficiently and last longer if you perform a few routine tasks.
The most common reason for water heater replacement is a leaking tank. Although leaks can occur for a host of reasons, the two most common ones are sediment buildup at the base of the tank and electrolysis. Sediment can cause excessive temperatures that stress the tank linking, and electrolysis will result in pinhole leaks in the tank's lining.

Remove sediment buildup at the base of the tank by flushing the tank at least once annually and more often if you have hard water. To flush the water heater, attach a garden hose to the drain valve at the base of the tank and run the hose out to a location where hot water can be safely drained. Turn the valve on and allow it to run for several minutes -- until the water becomes clear. Since you will be dealing with hot water, be careful not to get burned.

For water heaters that have not been flushed in ages (those that might have much sediment at the base of the tank), we suggest using a chemical additive that will help dissolve the sediment and facilitate the flushing process. Such a chemical can be found in the plumbing or water heater section or your local hardware store or home-improvement center. Another excellent resource is a plumbing supply house that sells to the trade.

Use the chemical in strict accordance with the directions on the label. Usually the cold-water supply valve to the water heater will need to be turned off and the supply line removed from the top of the water heater so that the solutions can be poured into the water heater. After a time -- usually several hours -- the water heater can be flushed as described earlier.

Another sediment-busting technique that is being used by many water heater manufacturers is a curved dip tube. The dip tube is a small-diameter plastic pipe that carries water from the cold-water inlet at the top of the water heater to within 12 inches or so of the base of the tank where the burners are located. A curve at the end of the dip tube (placed at the proper angle) will create a swirling action that will help reduce sediment buildup and assist in the flushing process.

Pinhole leaks in the tank lining are prevented by a cathodic or ``sacrificial'' anode that is located inside the tank. It is a vertical rod with a hex head that runs from the top of the tank to within about a foot of the base. As its name implies, the anode is designed to give itself up to protect the integrity of the tank. Depending on its composition (zinc, magnesium or aluminum), the water quality and whether you have a water softener, an anode can require replacement as often as once a year. An anode should, however, last about three years. A replacement anode can be found in the water heater-plumbing section of your local hardware store or home center or at a plumbing supply store that sells to the trade. Removal and replacement can be a daunting task that might best

Water at the base of a tank is not always the result of a leaking tank and, thus, will not necessarily require replacement. A leaking water connection that might not be visible at the top of the tank can trickle down the outside (inside the outer shell of the tank) and show itself as a puddle of water on the floor below the tank. Careful inspection of the various connections using a dry towel and a flashlight might reveal a leak that can easily be repaired with a wrench in a matter of seconds.

The hot- and cold-water connections at the top of the water heater usually are made with flexible copper supply lines that are attached to the water heater with short lengths of pipe called *******. Brass ******* and or dielectric unions should be used to prevent electrolysis. In addition, all pipe threads should be wrapped with Teflon tape or a similar material that prevents leaks.

Another likely location for a leaking water heater is the temperature and pressure relief valve (TP&R valve). The TP&R valve is a safety valve that is designed to open when the water in the tank becomes too hot or the pressure in the tank becomes excessive. The valve is attached to the tank by a threaded connection. Like the water supply connections at the top of the water heater, the TP&R connection can leak. The valve must be removed, the threads wrapped with Teflon tape, and then reinstalled to stop the leak. A faulty TP&R valve can be another, more serious, cause for a leak. A leaking TP&R valve should immediately be replaced to prevent a potential explosion.

The drain valve is another primary location on a leaking water heater. Unfortunately, most manufacturer-installed valves are of poor quality. Consequently, the valve can be difficult to operate and can leak at the spigot or at the location where it is connected to the tank. Therefore, we suggest replacing the cheaply manufactured gate valve with a high-quality brass-ball valve that can be easily operated. The ball valve will also facilitate the flushing process by improving the volume of water allowed to exist in the tank during the flushing process. Since a ball valve is opened and closed with a right angle turn, we suggest that you install a brass cap on the discharge port of the valve to prevent accidental operation that can result in burning or a flood.

Be alert to your water heater's needs and it will give you many years of energy-efficient, dependable service.
 
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brewchief

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Pattenp, the customer has flushed the tank at least yearly when we do other maintenance on his a/c and furnace, in the past we have pulled anode rods and they are definitely eroded but still have life left. The last time i spent a good amount of time testing the grounds for voltage and currant with nothing to show for it, at this point some ground wire and clamps would be worth it even if it is a shot in the dark.
I've installed hundreds of water heaters and never run into something like this, I'm baffled.

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pattenp

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What is the exact failure? Failed fitting, tank leak due to rust through? Is it the same kind of failure every time?
 

sberry

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Its already grounded thru the electric, I would think thats as good as it gets, lots of people have their own pet theories, most don't mean much, some are outright dangerous.
 
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brewchief

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Failure is rust pinholes in the tank, no problems at the fittings.
I would think it should be grounded well already but I'm willing to try something if it has any chance of fixing it.
We have tons of other customers on the same water system with no issues so we belive it has to be something to do with the house

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pattenp

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Is it the same tank brand and model that failed every time? Just wondering if it could be a defect in a manufacturing run and you were just unlucky to get them.
 

wyliesdiesels

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Definitely a weird one! I'm out of ideas. The tech guy doesn't know what he's talking about. If there is no stray currents on the plumbing, then I don't see how grounding/bonding the plumbing @ the heater will fix anything!
 
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coolreed

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Sounds like you may be talking about an electric heating element failing. Grounding your hot water line is not going to help. Most electric heater utilize 220 VAC in which case you should have two hot leads, a neutral, and a ground. Hopefully, the maintenance personnel are not wiring a 110 VAC heater with 220 VAC. In which case the element will not last long.
 

wyliesdiesels

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Sounds like you may be talking about an electric heating element failing. Grounding your hot water line is not going to help. Most electric heater utilize 220 VAC in which case you should have two hot leads, a neutral, and a ground. Hopefully, the maintenance personnel are not wiring a 110 VAC heater with 220 VAC. In which case the element will not last long.

Dude, did u read the post? Its a gas fired heater! Nice try!
 
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brewchief

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Tech guy is full of it. There should be ZERO current on that ground wire and ground rod system. It is there for lightning mainly, not anything much else. The house would function just fine without it and be just as safe too (except for lightning.)

What is a ground wire going to do? It is already bonded/grounded.

Another ground rod might help if lightning hits it.

If that heater is hot, as in current is flowing through it because the copper in the house is hot, you should be able to figure that out. That is a stay current problem, NOT a ground problem. Grounding the tank another time isn't going to do anything about that stray current. It is already grounded through the cold water bond, which is where stray current, if present, may be coming from.

No one understands grounds, they think they are some magic.

Are you getting shocked at the heater when you disconnect the water line? Any history of shocks at the house from touching the plumbing when wet? Do you have a clamp? Can you clamp the incoming water line to see if it is carrying any current? If it is, that is your problem. Fixing that may require an isolation bushing on the main water line.

I have not put my clamp meter on the water line, I will try that if I go back, I'm not 100% my clamp will fit as the incoming line looks to be 1 1/4" copper.

Is it the same tank brand and model that failed every time? Just wondering if it could be a defect in a manufacturing run and you were just unlucky to get them.

I don't remember what brand the original heater was, pretty sure the first one I put in was an AO Smith, that was followed by a Lochivar that was made by Bradford White, we just installed a new Lochivar that is now made by AO Smith.

All the heaters we have installed have been 50 gallon sealed combustion two pipe power vent natural gas.

The house(I called it a condo before but it's really a house that they don't have to do outdoor maintenance on) is in a large subdivision of probably 1500-2000 houses and condos, they are on either city water or community well(I forget which). We have a ton of customers in the area and none of them have had issues like this, water in the area is not great but 10-12 years is more of the average lifespan for a water heater around here, I ran across one in the same sub a few weeks ago that was 27 years old and still working fine.

I've talked to the tech line guys in the past and they have brought up grounding before so I think there might be something to it, we would at least like to try something.
 

Socophreak

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If the unit isn't grounded then grounding will help, but if it's already grounded then more grounding shouldn't change your issue.

Have you checked the water itself at all? I see you mentioned a softener, is the softener before the heater? Things like alkalinity and salt in water can cause havoc on systems. I've seen stainless steam boilers eaten through because of things like this.

The real thing to look at is, what is different between this system and all the other systems that are lasting much longer.
 

wyliesdiesels

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And electric water heaters are normally 240, 2 current carrying conductors and a ground.

Darn. I dunno how I missed that!

If the unit isn't grounded then grounding will help, but if it's already grounded then more grounding shouldn't change your issue.

Have you checked the water itself at all? I see you mentioned a softener, is the softener before the heater? Things like alkalinity and salt in water can cause havoc on systems. I've seen stainless steam boilers eaten through because of things like this.

The real thing to look at is, what is different between this system and all the other systems that are lasting much longer.

Grounding is NOT going to fix this problem. We've already established that. Read what Mr. Mark posted above. The absence of grounding or bonding of the H2o heater piping will not cause the tank to fail prematurely! The tank in my place does not have bonding and its 15+ yrs old and still kicking.

Most people don't understand grounding! Bonding, grounds, and ground rods are for 2 things- to try to protect against/discharge lightning strikes(notice I said try- it doesn't always work) and to provide a path for fault current so breakers can open during a fault!

I'm curious what your line of thinking is. Why do u think the addition of grounding/bonding @ the H2o heater piping will keep the tank from failing prematurely?
 
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brewchief

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I'm grabbing at straws.... but is the water being over softened, causing the anode rod not to do it's job?

On one of the previous failures we thought the same thing, water tested good.
That time IIRC we also had an electrician come out to verify the grounding and to insure there were no loose neutrals etc.

Tech support guys stressed adding grounds, said they have seen the same thing before and it fixed it, maybe it did and maybe people just bought a different brand heater, I think we will end up bonding the **** out of everything and then wait 3 years to see if it fixes it.
 

wyliesdiesels

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A sacrificial anode's life depends on the quality of the water, the amount of use the tank gets, the water temperature, and the quality of the tank -- meaning how well it was constructed. When salt is added to the water (as in softened water), anodes corrode more quickly. Water softeners help reduce sediment, but anodes can corrode in as little as six months if the water is over-softened. Do not soften to zero. Leave 50-120 ppm of hardness.

People occasionally ask us if pipe-seal tape applied to the threads of the anode blocks the electrolytical reaction. Tanks we've serviced repeatedly usually have corroded anodes. We've tested with a multimeter and found current flowing between the anode and the tank, despite the tape.

Not sure if this is useful....
 

Socophreak

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Darn. I dunno how I missed that!



Grounding is NOT going to fix this problem. We've already established that. Read what Mr. Mark posted above. The absence of grounding or bonding of the H2o heater piping will not cause the tank to fail prematurely! The tank in my place does not have bonding and its 15+ yrs old and still kicking.

Most people don't understand grounding! Bonding, grounds, and ground rods are for 2 things- to try to protect against/discharge lightning strikes(notice I said try- it doesn't always work) and to provide a path for fault current so breakers can open during a fault!

I'm curious what your line of thinking is. Why do u think the addition of grounding/bonding @ the H2o heater piping will keep the tank from failing prematurely?

You are right. Grounding will do nothing. If there is grounding, adding more won't help at all.
 

MrMark

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The thing is you can't really unground a water heater with a copper pipe system without trying pretty hard. So you could add all the grounds in the world and it wouldn't matter. That thing is grounded as good as you possibly could ground it through that pipe, which is connected to service neutral. All that bond does is provide a path for stray mains current to flow (not much, but some). It seems to me that grounding is the opposite of what you want. In other words, grounding could never solve your problem but it could cause it.

I would try ungrounding it if I could by adding a plastic ****** or bushing.

We actually did that here on my home system. I had the city special order some isolation bushings for the water meter to decouple the main line from my copper supply pipe. The whole main line carries parallel path neutral current back to the transformer and it can come into your house through the plumbing to seek a return through the service neutral. The bushing was recommended by Edison and solved the problem. The main line is essentially a parallel path conductor and carries a good bit of current. THe water meter guys get shocked all the time.

The water softener seems to be the suspect party here.
 
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wyliesdiesels

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The thing is you can't really unground a water heater with a copper pipe system without trying pretty hard. So you could add all the grounds in the world and it wouldn't matter. That thing is grounded as good as you possibly could ground it through that pipe, which is connected to service neutral. All that bond does is provide a path for stray mains current to flow (not much, but some). It seems to me that grounding is the opposite of what you want. In other words, grounding could never solve your problem but it could cause it.

I would try ungrounding it if I could by adding a plastic ****** or bushing.

We actually did that here on my home system. I had the city special order some isolation bushings for the water meter to decouple the main line from my copper supply pipe. The whole main line carries parallel path neutral current back to the transformer and it can come into your house through the plumbing to seek a return through the service neutral. The bushing was recommended by Edison and solved the problem. The main line is essentially a parallel path conductor and carries a good bit of current. THe water meter guys get shocked all the time.

The water softener seems to be the suspect party here.

My thoughts exactly! If the plumbing is indeed acting as a parallel return path back to the transformer, adding bonding could INCREASE the electrolysis rate and further decrease the tanks life span.

I would check for current on the plumbing as well as check the water softener settings and test the water!
 
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