# Di-electric unions



## redbeardplumber (Dec 4, 2012)

I started a 75 gallon HWT install at about 5pm today. Went pretty good except for the drywall scuff I put in the wall ( I will fix). Forgot that the outlets r 1" NPT.... Damn everything closed, check van ok I have 1" Di -electric unions. Even though I don't like them, I can complete job. Do the regular triple check before I go. All good....
I live 30 miles away and I get home and a text saying there is a pin-hole leak in solder at the Di-electric......Aargh. Stupid things. I don't know when the last time I had a solder leak 1 hr after pressurizing. Damn.


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## Plumberman (Jul 7, 2008)

How is it the dielectric unions fault?


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## Flyout95 (Apr 13, 2012)

redbeardplumber said:


> I started a 75 gallon HWT install at about 5pm today. Went pretty good except for the drywall scuff I put in the wall ( I will fix). Forgot that the outlets r 1" NPT.... Damn everything closed, check van ok I have 1" Di -electric unions. Even though I don't like them, I can complete job. Do the regular triple check before I go. All good.... I live 30 miles away and I get home and a text saying there is a pin-hole leak in solder at the Di-electric......Aargh. Stupid things. I don't know when the last time I had a solder leak 1 hr after pressurizing. Damn.



Why would you hate a di-electric? Sounds like you need to solder a little better.


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## redbeardplumber (Dec 4, 2012)

Ha.... Oh it's my bad.... If I had FIP's I know I would've been good. Just seem to be my nemesis, usually I get a bit of solder roll onto the face of those unions. Don't use them a lot maybe there is a trick I don't know about.


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## 422 plumber (Jul 31, 2008)

Do you clean the pipe and the brass socket of the dielectric? They are lead free now, so you have to be careful and don't overheat them.


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## redbeardplumber (Dec 4, 2012)

^^^^^ I did, maybe it got a bit hot. So gotta keep the heat down with the brass now?


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## redbeardplumber (Dec 4, 2012)

Flyout95 said:


> Why would you hate a di-electric? Sounds like you need to solder a little better.


I think I do pretty well thanks, my success rate it at least 75%. lol


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## 422 plumber (Jul 31, 2008)

redbeardplumber said:


> ^^^^^ I did, maybe it got a bit hot. So gotta keep the heat down with the brass now?


Not keep the heat down, only keep the heat there as long as necessary. That's why cleaning is so important, it takes less time to make a clean joint than dirty joint. Also, you used to be able to keep your flame at one side of a fitting and just roast it, till the solder sucked in on the other side. Not now, with LF brass, you need to roll your flame around the joint and when it's done, it's done. It's easy to overheat, and with the new water safe fluxes, it's a new paradigm.


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## Master Mark (Aug 14, 2009)

*time released leaks....*

arent the nipples on top of the heater already dia-electric???


having a pin hole leak on a solder fitting an hour after the job ,,,,, that is called a timed released leak.... 

most of mine only happen on a Friday at around 6 pm... normally the heater has sat all day long before it begins to leak.. and I am already home'


to be able to solder something just good enough to last the whole day and then only begin to leak when you are already at home....... . 

 that is a skill that cannot be taught.... a talent, a gift....:laughing:.


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## redbeardplumber (Dec 4, 2012)

Master Mark said:


> arent the nipples on top of the heater already dia-electric???
> 
> 
> having a pin hole leak on a solder fitting an hour after the job ,,,,, that is called a timed released leak....
> ...


Yes always when you get home...

Standard mi 75 Bradford white. Are HWT nipples considered Di-electric... They have the plastic sleeve inside them. I usually use FIP, but it's all I had on truck.


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## 422 plumber (Jul 31, 2008)

Our shop is mostly pipefitters, and they do a lot of work at refineries that calls for stainless steel pipe and fittings. They have a conex filled with all kinds of goodies left over from jobs. I raid it from time to time and I always have stainless nipples and fittings on my truck. Most of our water up here is hard, so I have discovered that the best thing for heaters is to remove the factory nipples and install stainless nipples, then use bradd or stainless ground joint unions to tie into the copper with.


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## crown36 (May 21, 2013)

redbeardplumber said:


> I started a 75 gallon HWT install at about 5pm today. Went pretty good except for the drywall scuff I put in the wall ( I will fix). Forgot that the outlets r 1" NPT.... Damn everything closed, check van ok I have 1" Di -electric unions. Even though I don't like them, I can complete job. Do the regular triple check before I go. All good....
> I live 30 miles away and I get home and a text saying there is a pin-hole leak in solder at the Di-electric......Aargh. Stupid things. I don't know when the last time I had a solder leak 1 hr after pressurizing. Damn.


 Happens to the best of us. I'm sure you already corrected the issue.


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## LIQUID (Sep 26, 2013)

the nipples are NOT di electric. you need di electric unions on all hwt's also, this is a solder issue not a union issue. use silver soldier ( easyer to work with that 95-5 IMO ) and wipe your joint with yourt fire blanket while the solder is cooling but still running ( or a piece of insulation ) it gives it a smooth and machiene made looking finish ( try it and you will see what I mean ). solder more... lots more and you wont have this issue ( not trying to offend ) and as a final piece of advice.. 

after pressurizing and running the tank smack the pipes around ( not too bad ) with the rubber handle of your hammer or channel locks etc. the idea is that you put the pipes under waaaay more stress that they would ever see in service... if they don't leak at all then then they wont ever.


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## LIQUID (Sep 26, 2013)

and if you are talking about FIP x copper fittings then this is not a correct installation. you NEED di electric, FIP x CU is not a di electric connection. personally I hate the flexi connectors ( made for hwt's ) as they will leak over time on the ridges.


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## bct p&h (Jan 19, 2013)

422 plumber said:


> Do you clean the pipe and the brass socket of the dielectric? They are lead free now, so you have to be careful and don't overheat them.


A lot of brass parts are coming through with a coating to keep the lead from leaching into the water instead of making the part lead free. If you don't clean them really well the coating will foul the solder joint and make a leak.


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## wyrickmech (Mar 16, 2013)

What is a hwt I have never heard a plumber use this term. We where talking about water heaters I assume you mean wh,s


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## TX MECH PLUMBER (May 27, 2011)

Get some of this !!!!

I will be soldering 3 2" dielectric unions tomorrow for a storage tank Il report back. On how it went. 

I did have a drip on a 3/4 ball valve. The other day. Happens to the best of us 

I too bang my pipe around to stress it

I wouldn't sil flos the union tho. U can't sil flos the brass ball valves so why do it on the union ! 

My 2 cents


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## TX MECH PLUMBER (May 27, 2011)

.... Oops


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## TX MECH PLUMBER (May 27, 2011)

wyrickmech said:


> What is a hwt I have never heard a plumber use this term. We where talking about water heaters I assume you mean wh,s


When you have a boiler that feeds a storage tank some guys call them hot water tanks. I call them storage tanks. But you only see them in large buildings around here It's more common up north where they use the boiler and storage tank for potable water and heating


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## LIQUID (Sep 26, 2013)

yeah, Hot W ater T ank.. where I live the term is generic referring to a vessel storing and or heating hot water. also a water heater on a print here is labled H.W.T. 


yes water heate, hot water tank .... potato potatoe


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## LIQUID (Sep 26, 2013)

TX MECH PLUMBER said:


> Get some of this !!!!
> 
> I will be soldering 3 2" dielectric unions tomorrow for a storage tank Il report back. On how it went.
> 
> ...


if you use or have a fire blanket ( or can get a small piece of fiberglass house insulation or pipe etc. ) try wiping the joint as I said with it.. makes is Soooo beautiful, Ive been complimented many times on how nice my soldering is .


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## TX MECH PLUMBER (May 27, 2011)

Even on the soft solder joint ?


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## Plumberman (Jul 7, 2008)

TX MECH PLUMBER said:


> Even on the soft solder joint ?


You can't wipe a sil fos joint silly..


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## TX MECH PLUMBER (May 27, 2011)

I never have. But liquids earlier post implied he does wipe a brazed joint 

I never wipe a joint when its hot after it cools I wipe it with a wet soapy rag. And don't ever wipe it with a flux brush while its hot. Ever


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## Plumberman (Jul 7, 2008)

I don't wipe sil fos either...

Little hot for all that. Ill knock the black off when it cools...


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## Ghostmaker (Jan 12, 2013)

LIQUID said:


> the nipples are NOT di electric. you need di electric unions on all hwt's also, this is a solder issue not a union issue. use silver soldier ( easyer to work with that 95-5 IMO ) and wipe your joint with yourt fire blanket while the solder is cooling but still running ( or a piece of insulation ) it gives it a smooth and machiene made looking finish ( try it and you will see what I mean ). solder more... lots more and you wont have this issue ( not trying to offend ) and as a final piece of advice..
> 
> after pressurizing and running the tank smack the pipes around ( not too bad ) with the rubber handle of your hammer or channel locks etc. the idea is that you put the pipes under waaaay more stress that they would ever see in service... if they don't leak at all then then they wont ever.


The stainless steel nipples with the plastic lining are Dielectric nipples and supplied by most HWT manufactures. 
A link on them
http://waterheaterreviews.com/what-is-a-dielectric-nipple

Many water heaters are supplied with Dielectric Nipples and in many cases the supplied Dielectric Nipples are also heat traps which can limit heat loss from a water heater. The Dielectric Nipples are essentially a short piece of pipe, which is threaded at each end, and constructed with plastic lining the inside surface of the nipple which prevents the water or, electrolyte from contacting the metal. This failure of the water to contact the metal stops the galvanic corrosion from occurring. Care must be taken with the female adapter that threads onto the Dielectric Nipple to ensure that the water is not able to touch both the nipple and adapter where they connect to avoid corrosion problems.


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## Plumbworker (Oct 23, 2008)

Dielectric unions in my opinion should have no place in any plumbing system EVER! Most of them are cheaply made in asia with poor zinc plated steel they clogg and rust out within a few months the rubber gaskets are rubbish, if you have to disconnect a dielectric union on a repair or service call you better be perpeared to replace it as the gasket is most likely toast and will leak when you attempt to reassemble you dont have that issue with brass ground joint unions.. I have many installs with just brass unions attached to the nipples on the hot water tank, i even service some of those installs yearly i've broken the unions without a lick of rust clogging the waterway i can say every water heater i've ever replaced with dielectric unions installed they were damn near clogging the entire waterway from that cheap ass zinc plate bull crap..


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## wyrickmech (Mar 16, 2013)

Plumbworker said:


> Dielectric unions in my opinion should have no place in any plumbing system EVER! Most of them are cheaply made in asia with poor zinc plated steel they clogg and rust out within a few months the rubber gaskets are rubbish, if you have to disconnect a dielectric union on a repair or service call you better be perpeared to replace it as the gasket is most likely toast and will leak when you attempt to reassemble you dont have that issue with brass ground joint unions.. I have many installs with just brass unions attached to the nipples on the hot water tank, i even service some of those installs yearly i've broken the unions without a lick of rust clogging the waterway i can say every water heater i've ever replaced with dielectric unions installed they were damn near clogging the entire waterway from that cheap ass zinc plate bull crap..


we used to use water heater unions they were male iron pipe thread by sweat all brass. Never had a problem with the set up.


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## LIQUID (Sep 26, 2013)

Ghostmaker said:


> The stainless steel nipples with the plastic lining are Dielectric nipples and supplied by most HWT manufactures.
> A link on them
> http://waterheaterreviews.com/what-is-a-dielectric-nipple
> 
> Many water heaters are supplied with Dielectric Nipples and in many cases the supplied Dielectric Nipples are also heat traps which can limit heat loss from a water heater. The Dielectric Nipples are essentially a short piece of pipe, which is threaded at each end, and constructed with plastic lining the inside surface of the nipple which prevents the water or, electrolyte from contacting the metal. This failure of the water to contact the metal stops the galvanic corrosion from occurring. Care must be taken with the female adapter that threads onto the Dielectric Nipple to ensure that the water is not able to touch both the nipple and adapter where they connect to avoid corrosion problems.


hmmm interesting, never knew this// though I still have never had an issue with unions.


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## LIQUID (Sep 26, 2013)

TX MECH PLUMBER said:


> I never have. But liquids earlier post implied he does wipe a brazed joint
> 
> I never wipe a joint when its hot after it cools I wipe it with a wet soapy rag. And don't ever wipe it with a flux brush while its hot. Ever


 
no, not a brazed joint a solderd joint. and yes, never use a flux brush as it turns the pipe green after and is generally no good. try the fire blanket or insulation thing and you will likely give up the wet rag, I did anyways.


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## mccmech (Jul 6, 2011)

Whoa, hold on there fella. While I get that you personally may not wipe, or should I say clean a soldered joint with flux, there are plumbers out here who do it regularly. Firstly, when done properly, it will NOT turn the pipe green. Secondly, it gives a very clean, professionallook to the soldered joint. The steps should be 1) allow the solder to frost, 2) wipe the fitting& joints with the flux, 3) use yer rag to wipe the flux off the fitting & joints. It'll amaze you how sexy yer work will look if ya follow step 3. Just my .02 but I know my work looks crisp when I'm done!


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## justme (Jul 4, 2012)

wyrickmech said:


> What is a hwt I have never heard a plumber use this term. We where talking about water heaters I assume you mean wh,s



HWT = hot water tank


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## Best Darn Sewer (Dec 23, 2012)

Plumbworker said:


> Dielectric unions in my opinion should have no place in any plumbing system EVER! Most of them are cheaply made in asia with poor zinc plated steel they clogg and rust out within a few months the rubber gaskets are rubbish, if you have to disconnect a dielectric union on a repair or service call you better be perpeared to replace it as the gasket is most likely toast and will leak when you attempt to reassemble you dont have that issue with brass ground joint unions.. I have many installs with just brass unions attached to the nipples on the hot water tank, i even service some of those installs yearly i've broken the unions without a lick of rust clogging the waterway i can say every water heater i've ever replaced with dielectric unions installed they were damn near clogging the entire waterway from that cheap ass zinc plate bull crap..


Right on, brother. I agree completely. Every complaint you mention is exactly what I've observed. I haven't used dielectric unions for any reason on a domestic water system for at least 5 years, now, except when I lived in Montana, but only for WHs as the water there didn't destroy them nearly as bad as it does here in Houston.


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## plumbarius (Aug 19, 2013)

What Is a Dielectric Nipple?
By JOSEPH GIONORRO | Published: FEBRUARY 3, 2011


A Dielectric Nipple is used to help prevent corrosion of the steel tank of the water heater caused by galvanic corrosion when dissimilar metals such as copper are used for pipes connecting to the water heater. Galvanic corrosion can occur when two different metals contact each other in an electrolyte solution. Metals are ranked on a nobility scale and the further apart the two metals are in nobility the more likely they are to corrode. Copper and steel are far enough apart that damaging corrosion can occur in many cases. Water acts as the electrolyte solution and depending on water conditions there may be either almost no corrosion or, major corrosion that occurs when copper and steel are connected.

Many water heaters are supplied with Dielectric Nipples and in many cases the supplied Dielectric Nipples are also heat traps which can limit heat loss from a water heater. The Dielectric Nipples are essentially a short piece of pipe, which is threaded at each end, and constructed with plastic lining the inside surface of the nipple which prevents the water or, electrolyte from contacting the metal. This failure of the water to contact the metal stops the galvanic corrosion from occurring. Care must be taken with the female adapter that threads onto the Dielectric Nipple to ensure that the water is not able to touch both the nipple and adapter where they connect to avoid corrosion problems.


I would say that the nipples on the water heater would definitely be the correct connection. Especially if they are "dielectric" with the plastic lining. Just a shot in the dark.....


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## Ghostmaker (Jan 12, 2013)

plumbarius said:


> What Is a Dielectric Nipple?
> By JOSEPH GIONORRO | Published: FEBRUARY 3, 2011
> 
> 
> ...



So far they appear to work much better then the old style Dielectric union. Not to mention they come with the water heater.


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## LIQUID (Sep 26, 2013)

I'm suprsed so many have had issues with the unions.. I have never had an issue personally. Regardless there are many ways to the end and whatever works for you.


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## TX MECH PLUMBER (May 27, 2011)

mccmech said:


> Whoa, hold on there fella. While I get that you personally may not wipe, or should I say clean a soldered joint with flux, there are plumbers out here who do it regularly. Firstly, when done properly, it will NOT turn the pipe green. Secondly, it gives a very clean, professionallook to the soldered joint. The steps should be 1) allow the solder to frost, 2) wipe the fitting& joints with the flux, 3) use yer rag to wipe the flux off the fitting & joints. It'll amaze you how sexy yer work will look if ya follow step 3. Just my .02 but I know my work looks crisp when I'm done!


I prefer not to wipe with flux cause it gets my flux dirty and ruins brushes. The brushes suck bad enuf these days. I always spray it down with soapy water or a soapy rag. But don't wipe it when hot. Cooling the pipe/fitting/brass to fast weakens the material All I do is flick the drip off with the solder or me finger. Let cool then clean


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## MTDUNN (Oct 9, 2011)

TX MECH PLUMBER said:


> I prefer not to wipe with flux cause it gets my flux dirty and ruins brushes. The brushes suck bad enuf these days. I always spray it down with soapy water or a soapy rag. But don't wipe it when hot. Cooling the pipe/fitting/brass to fast weakens the material All I do is flick the drip off with the solder or me finger. Let cool then clean


I used to use gasoline to clean fittings. It worked great. But then there was that fire...


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## retired rooter (Dec 31, 2008)

Does anyone remember when solder changed from 50/50 to 95/5 ?B boy I almost had some bad problems from leaks!! I was lucky, I put in 5 watts 25 aubs prv on 1 street and 4 had pin hole leaks!! Turned out it was bad solder, some of my friends (other plumbers) had insurance claims that went back to the manufacture of the solder. I was lucky all my jobs were in homes that had dirt crawl spaces, Wish I could remember the year?:whistling2: Help REDWOOD you usually come to rescue and remember stuff I forget:no:


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## wyrickmech (Mar 16, 2013)

retired rooter said:


> Does anyone remember when solder changed from 50/50 to 95/5 ?B boy I almost had some bad problems from leaks!! I was lucky, I put in 5 watts 25 aubs prv on 1 street and 4 had pin hole leaks!! Turned out it was bad solder, some of my friends (other plumbers) had insurance claims that went back to the manufacture of the solder. I was lucky all my jobs were in homes that had dirt crawl spaces, Wish I could remember the year?:whistling2: Help REDWOOD you usually come to rescue and remember stuff I forget:no:


wasn't it 85 or86 I remember the change over it sucked. We used to solder large copper with 95/5 and cap the joint with 50/50. Worked good until they shut the use down.


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## MTDUNN (Oct 9, 2011)

Wasn't it the same year of the water conservation act? I think 1989


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## wyrickmech (Mar 16, 2013)

MTDUNN said:


> Wasn't it the same year of the water conservation act? I think 1989


 EPA safe water act was 91 I thought it was earlier to


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## redbeardplumber (Dec 4, 2012)

Like many have said here, I don't like the Di-electric for reasons givin... Only reason was it was late and it's all I had on the van.

When I took it apart the joint looked good, so being stubborn I cleaned and resoldered the stupid thing.... Still leaked..... Again I tried looked beautiful, again it leaked.... Ok I give up..... 1" FIP....


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## Plumborg (Feb 21, 2013)

mccmech said:


> Whoa, hold on there fella. While I get that you personally may not wipe, or should I say clean a soldered joint with flux, there are plumbers out here who do it regularly. Firstly, when done properly, it will NOT turn the pipe green. Secondly, it gives a very clean, professionallook to the soldered joint. The steps should be 1) allow the solder to frost, 2) wipe the fitting& joints with the flux, 3) use yer rag to wipe the flux off the fitting & joints. It'll amaze you how sexy yer work will look if ya follow step 3. Just my .02 but I know my work looks crisp when I'm done!


I was tought to never apply flux or wipe a joint while it is still hot. My apprentice class had a man from the CDA come and teach us how to solder. It was very informative, because there are so many variations of soldering techniques and "tricks" people came up with over time. And technically according to our code any copper that has not been installed according to the CDAs recommended techniques is an illegal install. Just my two cents as an apprentice in Chicago. 

http://www.copper.org/consumers/copperhome/DIY/doityourself_solderingschool.html


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## gordyloo (Dec 7, 2013)

I was taught to finish rough joints by brushing with flux or wiping with a dry jersey glove.


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## LIQUID (Sep 26, 2013)

Wipe with fire blanket or insulation.. looks awesome, doesn't turn green.


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## gear junkie (Jun 20, 2008)

Dielectrics suck. Here's a perfect example. Galv nipple had a little corrosion....flip it over and see the dielectric side. Forget that. I use a 6" brass nipple.


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## Best Darn Sewer (Dec 23, 2012)

gear junkie said:


> Dielectrics suck. Here's a perfect example. Galv nipple had a little corrosion....flip it over and see the dielectric side. Forget that. I use a 6" brass nipple.


Yup. I used dielectrics for the first few years I did repair work and then I went back to a few houses where I had used them and saw exactly what you are seeing in your pics. Since '06 I have used brass nipples as transitions to copper instead of dielectrics. I haven't used a dielectric in many years. I couldn't believe how much corrosion that builds up in the nipples and the dielectrics.


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## wyrickmech (Mar 16, 2013)

Best Darn Sewer said:


> Yup. I used dielectrics for the first few years I did repair work and then I went back to a few houses where I had used them and saw exactly what you are seeing in your pics. Since '06 I have used brass nipples as transitions to copper instead of dielectrics. I haven't used a dielectric in many years. I couldn't believe how much corrosion that builds up in the nipples and the dielectrics.


 correct me if I am wrong but you are not solving the problem. You still have dissimilar metals in direct contact. Brass and copper do not react with each other but brass and galvanized steel will. Don't get me wrong on heating loops I to use brass nipples to copper branches. Open loops like domestic water brings in fresh oxygen that compounds the process. A dielectric union is designed to break the conductivity between the two types of metals. It is more likely that somebody did not install it correctly and the metals were in contact. I had this situation on a addition where the heat lines were all copper and the connections were steel the crew on the roof making the final connection was cranking on the dielectric unions so hard they were pinching the rubbers. In this case they should have just put adapters on. The fact that the rubber is pinched means the dissimilar metals are in direct contact so the transition is lost. That may be what you are seeing at the transition in the pictures.


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## Rando (Dec 31, 2012)

gear junkie said:


> Dielectrics suck. Here's a perfect example. Galv nipple had a little corrosion....flip it over and see the dielectric side. Forget that. I use a 6" brass nipple.


Yes, IMO they cause more problems than they solve. I avoid them whenever I can and only use them if required by spec. Waterways are the way to go.


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## redbeardplumber (Dec 4, 2012)

What are waterways?


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## Rando (Dec 31, 2012)

redbeardplumber said:


> What are waterways?


The Galvy nipples with the plastic coating inside. Thats what we call them around here.


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## Plumb26 (May 18, 2013)

wyrickmech said:


> correct me if I am wrong but you are not solving the problem. You still have dissimilar metals in direct contact. Brass and copper do not react with each other but brass and galvanized steel will. Don't get me wrong on heating loops I to use brass nipples to copper branches. Open loops like domestic water brings in fresh oxygen that compounds the process. A dielectric union is designed to break the conductivity between the two types of metals. It is more likely that somebody did not install it correctly and the metals were in contact. I had this situation on a addition where the heat lines were all copper and the connections were steel the crew on the roof making the final connection was cranking on the dielectric unions so hard they were pinching the rubbers. In this case they should have just put adapters on. The fact that the rubber is pinched means the dissimilar metals are in direct contact so the transition is lost. That may be what you are seeing at the transition in the pictures.


I'll correct you, you are wrong. Brass nipple, coupling, or whatever is considered a dielectric connection. The connection between brass and galvanized will not have the same reaction as copper and galvanized. Better than dielectric unions would be a brass FIP X SWT union or if they would make the bottom part of union brass instead of galvanized, that too would solve problem.
I do think you are right about incorrect installations and/or overtightening.. If the plastic inserts that line the heat trap were to extend an inch or so, this would probably remedy the situation as well. :thumbsup:


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## Best Darn Sewer (Dec 23, 2012)

wyrickmech said:


> correct me if I am wrong but you are not solving the problem. You still have dissimilar metals in direct contact. Brass and copper do not react with each other but brass and galvanized steel will. Don't get me wrong on heating loops I to use brass nipples to copper branches. Open loops like domestic water brings in fresh oxygen that compounds the process. A dielectric union is designed to break the conductivity between the two types of metals. It is more likely that somebody did not install it correctly and the metals were in contact. I had this situation on a addition where the heat lines were all copper and the connections were steel the crew on the roof making the final connection was cranking on the dielectric unions so hard they were pinching the rubbers. In this case they should have just put adapters on. The fact that the rubber is pinched means the dissimilar metals are in direct contact so the transition is lost. That may be what you are seeing at the transition in the pictures.


Over tightening does cause issues and I have seen that before. You make a good point but here in Houston I have only seen 2 houses with boilers used for heating and they were both very old units on houses piped with galv. When I did work on boilers in Montana they would almost always have copper to the unit with little or no steel used for the connections and I don't recall dielectrics being issues on boilers. At least not that I recall. Honestly, I am not familiar enough with them and the issues that come with the piping for them as you.

The issues I see with them are on strictly domestic water and no heat loops or boiler systems. Brass is what most residential valves are made of and are connected to galv threads all the time. They work quite well as transitional connections, too. The dielectrics I have used that rotted out after a few years were mostly due to the galv nipple used on the female side. Maybe the MIP dielectrics are less likely to rot out but I still wont use them. I also think that it is the cheap quality of some brands of dielectrics that allow for the rapid corrosion. 

Now for hard piping water heaters with copper I have successfully used dielectrics many times but that is connecting copper to either dielectric nipples on the tank or to brass ones I install myself. 

If you use the brass as a transition from the copper to the galv than the two very dissimilar metals never touch. That is why Viega makes brass pro press MIPS to be used for connecting the copper to the steel. I have not seen issues with brass to copper to galv connections on domestic water ever. I am not saying that there aren't exceptions but I haven't seen any in 15 years...or I have forgotten about it which is very likely.


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## LBurk (Dec 23, 2013)

"The fittings at the cold water inlet and hot water​ outlet are dielectric waterway fittings with ¾ inch NPT male thread." This was taken directly out of the Bradford White install manual. (238-44943-00D Page 13.)

Nearly all of the water heater nipples today are considered to be die-electric. whether or not they truly are is debatable. 

Never touch a sweat joint until it has cooled enough for the solder to be solidified and don't quick quench with a wet rag. This can cause a joint to start cracking within the fitting cup and eventually work its way out. (Man I am so glad I never have done that - :whistling2: ) Always wipe all flux off the pipe and fittings when done. 

Class is done for today, have a great day! :thumbup: Okay I'll go away now....:blink:


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## 422 plumber (Jul 31, 2008)

My method is to use S.S. between galvanized and copper.

Sent from my iPhone using PlumbingZone


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## Best Darn Sewer (Dec 23, 2012)

422 plumber said:


> My method is to use S.S. between galvanized and copper.
> 
> Sent from my iPhone using PlumbingZone


What size and what fitting? Application? What's the cost like? I have wondered if SS was OK as a transition.


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## 422 plumber (Jul 31, 2008)

Best Darn Sewer said:
 

> What size and what fitting? Application? What's the cost like? I have wondered if SS was OK as a transition.


S.S. is perfect. It is between carbon steel and copper on the metal nobility scale. Around my area, our water is very hard. It is very common to unscrew a Sloan screwdriver stop and the bottom 3 turns of the thread is rotted off. Same with angle stops. I get my stainless fittings for free by ganking them out of the pipe fitters storage trailers. They use a ton of them at the refineries.

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## 422 plumber (Jul 31, 2008)

It is all domestic water, and I will use 90's, couplings, nipples, whatever.

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## wyrickmech (Mar 16, 2013)

Best Darn Sewer said:


> Over tightening does cause issues and I have seen that before. You make a good point but here in Houston I have only seen 2 houses with boilers used for heating and they were both very old units on houses piped with galv. When I did work on boilers in Montana they would almost always have copper to the unit with little or no steel used for the connections and I don't recall dielectrics being issues on boilers. At least not that I recall. Honestly, I am not familiar enough with them and the issues that come with the piping for them as you. The issues I see with them are on strictly domestic water and no heat loops or boiler systems. Brass is what most residential valves are made of and are connected to galv threads all the time. They work quite well as transitional connections, too. The dielectrics I have used that rotted out after a few years were mostly due to the galv nipple used on the female side. Maybe the MIP dielectrics are less likely to rot out but I still wont use them. I also think that it is the cheap quality of some brands of dielectrics that allow for the rapid corrosion. Now for hard piping water heaters with copper I have successfully used dielectrics many times but that is connecting copper to either dielectric nipples on the tank or to brass ones I install myself. If you use the brass as a transition from the copper to the galv than the two very dissimilar metals never touch. That is why Viega makes brass pro press MIPS to be used for connecting the copper to the steel. I have not seen issues with brass to copper to galv connections on domestic water ever. I am not saying that there aren't exceptions but I haven't seen any in 15 years...or I have forgotten about it which is very likely.


 transition of galv to brass to copper does slow the proses but it does not stop it. The break must be complete if the electrical current can pass from one metal to another then it will slowly but steadily erode. SS would be harder to erode so that would be a posable substitute. Don't forget copper is classified as red brass and brass is classified as yellow brass two grades of the same family copper ore. I know this has been a subject of great debate and I agree with a lot of what has been said but the unless you break the path of currant on the pipe it will erode. I think we would be best served to find a system that slows the proses so the equipment being served outlasts the method used.


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## wyrickmech (Mar 16, 2013)

Plumb26 said:


> I'll correct you, you are wrong. Brass nipple, coupling, or whatever is considered a dielectric connection. The connection between brass and galvanized will not have the same reaction as copper and galvanized. Better than dielectric unions would be a brass FIP X SWT union or if they would make the bottom part of union brass instead of galvanized, that too would solve problem. I do think you are right about incorrect installations and/or overtightening.. If the plastic inserts that line the heat trap were to extend an inch or so, this would probably remedy the situation as well. :thumbsup:


 I do believe that dielectric has more to do with the electric path from one metal to another. I do not disagree with the method of brass nipple or some combination. We used to use what we called water heater unions it was simply a male thread by sweat union. They work great but I have when's in behind others and seen where the brass was brittle and difficult to work with after a few years. This is probably the same reason brass valves are difficult to deal with sometimes. Also there is one thing that we overlook that is quality of the parts has a lot to do with longevity.


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## rjbphd (Feb 5, 2010)

I just piped in copper male adt into galv fittings... end of the problems, no bs die electric unions crap.


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## Best Darn Sewer (Dec 23, 2012)

422 plumber said:


> S.S. is perfect. It is between carbon steel and copper on the metal nobility scale. Around my area, our water is very hard. It is very common to unscrew a Sloan screwdriver stop and the bottom 3 turns of the thread is rotted off. Same with angle stops. I get my stainless fittings for free by ganking them out of the pipe fitters storage trailers. They use a ton of them at the refineries.
> 
> Sent from my iPhone using PlumbingZone


Wow, stealing with aplomb. At least you openly admit to being a thief. I have more respect for that than someone who lies about it. I would never work with you for fear of my tools showing up missing but at least your honest about your stealing. I hate thieves of all types. Especially when they brag about stealing from the job site. By the way, that is why insurance costs so damn much. Because of people like you who feel its OK to steal from a company because they can absorb the cost.


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## 422 plumber (Jul 31, 2008)

Best Darn Sewer said:


> Wow, stealing with aplomb. At least you openly admit to being a thief. I have more respect for that than someone who lies about it. I would never work with you for fear of my tools showing up missing but at least your honest about your stealing. I hate thieves of all types. Especially when they brag about stealing from the job site. By the way, that is why insurance costs so damn much. Because of people like you who feel its OK to steal from a company because they can absorb the cost.


Sorry to break your bubble, but I am not a thief. Our shop is mostly pipefitters, with a few plumbers. We have shipping containers in our laydown yard that are crammed with fittings and material left over from jobs. This has all been paid for. The guys demob jobs and just toss buckets and boxes full of stuff in these conexes. My boss has okayed my "thievery." 
At least you didn't accuse me of being a hypocrite and typical Christian. 🙈🙉🙊

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## plbgbiz (Aug 27, 2010)

422 plumber said:


> Sorry to break your bubble, but I am not a thief. Our shop is mostly pipefitters, with a few plumbers. We have shipping containers in our laydown yard that are crammed with fittings and material left over from jobs. This has all been paid for. The guys demob jobs and just toss buckets and boxes full of stuff in these conexes. My boss has okayed my "thievery." At least you didn't accuse me of being a hypocrite and typical Christian. dde48dde49dde4a Sent from my iPhone using PlumbingZone


I dunno 422....

I've seen your face and you look pretty shifty to me. :laughing:


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## Best Darn Sewer (Dec 23, 2012)

422 plumber said:


> Sorry to break your bubble, but I am not a thief. Our shop is mostly pipefitters, with a few plumbers. We have shipping containers in our laydown yard that are crammed with fittings and material left over from jobs. This has all been paid for. The guys demob jobs and just toss buckets and boxes full of stuff in these conexes. My boss has okayed my "thievery."
> At least you didn't accuse me of being a hypocrite and typical Christian. ?de48?de49?de4a
> 
> Sent from my iPhone using PlumbingZone


Fair enough. I take back my harshness. I have been robbed and have had parts stolen so I get a little sensitive about stealing. When you only said that you ganked them from the pipe fitters trailer I could only assume you were straight up stealing them. Extra fittings that are paid for should be put into service. IMO that's better than scrapping them.


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## 422 plumber (Jul 31, 2008)

plbgbiz said:


> I dunno 422.... I've seen your face and you look pretty shifty to me. :laughing:


Yeah, I have got a face made for radio.

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## 422 plumber (Jul 31, 2008)

Best Darn Sewer said:


> Wow, stealing with aplomb. At least you openly admit to being a thief. I have more respect for that than someone who lies about it. I would never work with you for fear of my tools showing up missing but at least your honest about your stealing. I hate thieves of all types. Especially when they brag about stealing from the job site. By the way, that is why insurance costs so damn much. Because of people like you who feel its OK to steal from a company because they can absorb the cost.


I would never steal tools because that means I would have to work with them.

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## gear junkie (Jun 20, 2008)

Wow shortest arguement ever on PZ and it got resolved without moderators.


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## Best Darn Sewer (Dec 23, 2012)

Well, I had assumed a lot incorrectly. When the situation was explained in its entirety it was clear that the situation was not thievery. It was using up extra parts.


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