Galvanic corrosion

[eds54]

Hi All
Has anybody had a problem or even heard of Galvanic Corrosion. A house that was completed 2 years ago has started having water leaks. (I know this is a site for electricians) a water softener was recently fitted and the manufacturers have suggested that because the plumber has used a mixture of copper and plastic pipe there is no earth continuity throughout the pipes and possibly causing Galvanic Corrosion where the 2 join. Has anybody had this problem before an if so was there a solution other than cross bonding across the joints which I imagine even if the plumber could remember where they were would be a nightmare. I have never heard of this happening before so any help would be appreciated.

 

[LankyWill]

why would you need bonding then?

 

[eds54]

if you google galvanic corrosion it would be explained much better than i can do it

 

[Leesparkykent]

if you google galvanic corrosion it would be explained much better than i can do it

wouldn't it have to be two metals causing the reaction?

 

[timbobelfast]

I come accross Galvanic Corrosion a lot, generally when previous electricians have installed stainless steel junction boxes using steel or zinc fixings! The later starts to rust very rapidly.

It is a reaction between to dis-similar metals.

Can't see how this affects your situation OP.

 

[Pete999]

Hi All
Has anybody had a problem or even heard of Galvanic Corrosion. A house that was completed 2 years ago has started having water leaks. (I know this is a site for electricians) a water softener was recently fitted and the manufacturers have suggested that because the plumber has used a mixture of copper and plastic pipe there is no earth continuity throughout the pipes and possibly causing Galvanic Corrosion where the 2 join. Has anybody had this problem before an if so was there a solution other than cross bonding across the joints which I imagine even if the plumber could remember where they were would be a nightmare. I have never heard of this happening before so any help would be appreciated.

Not a Scientist, but a quick read of Galvanic Corrosion it states it happens between 2 metals, best read up on it yourself, just google Galvanic Corrosion there is plenty to choose from.

 

[LankyWill]

plus if its part metal and plastic there is no path to eart, ergo no bonding

 

[eds54]

Your right pete i did start to read about it on wikipedia but i,m just repeating what was said by the tech boys at the water softener manufacturers. they said they have had a few cases where the corrosion has happened between the two different pipes so i just thought i would ask.

 

[Pete999]

Your right pete i did start to read about it on wikipedia but i,m just repeating what was said by the tech boys at the water softener manufacturers. they said they have had a few cases where the corrosion has happened between the two different pipes so i just thought i would ask.

2 different pipes of different metals, not copper and PVC

 

[HandySparks]

Hi All
Has anybody had a problem or even heard of Galvanic Corrosion. A house that was completed 2 years ago has started having water leaks. (I know this is a site for electricians) a water softener was recently fitted and the manufacturers have suggested that because the plumber has used a mixture of copper and plastic pipe there is no earth continuity throughout the pipes and possibly causing Galvanic Corrosion where the 2 join. Has anybody had this problem before an if so was there a solution other than cross bonding across the joints which I imagine even if the plumber could remember where they were would be a nightmare. I have never heard of this happening before so any help would be appreciated.

I think it's unlikely to be galvanic corrosion.

Are the leaks through the wall of the copper pipe or are they at joints? If at joints are they plastic or metal, push-fit, compression or soldered?

 

[GBDamo]

Try a sacrificial Anode, usually a lump of Zinc (or metal that is more reactive than copper) that has to be submerged in the system and bonded to the pipework.

Monitor both the Anode for signs of corrosion and the pipework for continuing leaks. if no further leaks and the Anode starts to dissolve it was indeed Galvanic corrosion. If leaks continue and Anode stays unscathed the you'll have to look elsewhere.

Are you seeing pinholes in the pipe or failing joints? I only ask as I have seen multiple joint failures due to crap in flux.

 

[eds54]

All the information I have as come from a phone call apparently there are some leaks on the copper pipe which has soldered joints and the offending pipe was green inside.

Thanks to everybody who has taken time to to respond o this post

 

[ipf]

You're talking about creating electrolytic cells for galvanic corrosion, which would need two separate metals immersed....and a potential difference.
I can't see copper and plastic interacting in such a way.
Are any solutions having an affect on the copper?

Could have different metals with radiators, I suppose.....copper pipes, salty solution and a variance in potential. It would be a case of if it's metal....BOND IT.....back to 15th edition and earth cabling everywhere.:nonod:

 

[sam400]

Galvanic corrosion occurs in all domestic CH systems given the mix of copper pipes, steel radiators and aluminium heat exchangers,
The answer is normally a bottle of inhibitor!

 

[Marvo]

If a softener was fitted first thing to do would be to get the water salt content and ph level tested.