Is the copper piping in my kitchen grounded properly?

[DIYNotIan]

Hi all

Firstly, apologies if I am over worrying about this.... And secondly, apologies that I have no prior knowledge about the need to ground pipework and so might be missing something(s) obvious!

The water supply comes into our house through a WC next to the front door. There is an earth wire which looks like it goes outside. On the opposite wall is a sink, beneath which the two pipes (hot and cold) are connected with an earth and there are two "Do Not Remove, etc" metal tags. From my little knowledge, all seems well there.

The kitchen is at the back of the house and the mains water reaches the kitchen through a pipe that comes out of the flooring (floating floor). The pipe that comes out is the blue plastic PE MDPE type. I've no idea how long the run of that is because it is all under flooring. At the point where it comes out of the floor, it joins to copper piping which then feeds the kitchen sink. I can see no ground connection on any of that piping

Now this is where I might be in the 2+2 = 5 arena. But my query is that because there is plastic piping between the earthed copper pipes at point of entry and the piping in the kitchen, does that mean the kitchen pipes are not earthed? And if so is this something to worry about?

Cheers

Max

(PS - please move to electrics forum if that is more appropriate).

 

[EFLImpudence]

I have no prior knowledge about the need to ground pipework and so might be missing something(s) obvious!

You do not need to 'ground' - earth - pipework; you may have to 'bond' it because it is earthed, i.e. in the ground.

The water supply comes into our house through a WC next to the front door. There is an earth wire which looks like it goes outside.

It should run to the Main Earthing Terminal in or near the Consumer Unit.

On the opposite wall is a sink, beneath which the two pipes (hot and cold) are connected with an earth and there are two "Do Not Remove, etc" metal tags. From my little knowledge, all seems well there.

If there is no bath, shower etc. (basins don't count) these connections are not required although will do no harm.

The kitchen is at the back of the house and the mains water reaches the kitchen through a pipe that comes out of the flooring (floating floor). The pipe that comes out is the blue plastic PE MDPE type. I've no idea how long the run of that is because it is all under flooring. At the point where it comes out of the floor, it joins to copper piping which then feeds the kitchen sink. I can see no ground connection on any of that piping

Supplementary bonding is not required in kitchens.

Now this is where I might be in the 2+2 = 5 arena. But my query is that because there is plastic piping between the earthed copper pipes at point of entry and the piping in the kitchen, does that mean the kitchen pipes are not earthed?

It doesn't matter.
As long as the correct bonding is in place at the point of entry to the building then all is well.

And if so is this something to worry about?

No.

 

[PrenticeBoyofDerry]

If you have an incoming water supply of MDPE (blue plastic). Then there is no requirement to bond the water supply.

 

[JohnW2]

If you have an incoming water supply of MDPE (blue plastic). Then there is no requirement to bond the water supply.

True, but...

... the earthed copper pipes at point of entry...

Kind Regards, John

 

[flyingsparks]

If you have an incoming water supply of MDPE (blue plastic). Then there is no requirement to bond the water supply.

I know this has come up before, and I know if it'd plastic in the ground then there is in theory no way a potential difference can arise, but I am lead to believe even when supplied by plastic pipe, you should bond at the first bit of copper?

 

[EFLImpudence]

I know this has come up before, and I know if it'd plastic in the ground then there is in theory no way a potential difference can arise, but I am lead to believe even when supplied by plastic pipe, you should bond at the first bit of copper?

Some people read the regulation(s) like that but they usually have overlooked the principal deciding factor because it is not actually mentioned in 544.1.

That is: only extraneous-conductive-parts require (main) bonding 411.3.1.2.

If it is not then ...

 

[JohnW2]

I know this has come up before, and I know if it'd plastic in the ground then there is in theory no way a potential difference can arise, but I am lead to believe even when supplied by plastic pipe, you should bond at the first bit of copper?

Some people read the regulation(s) like that but they usually have overlooked the principal deciding factor because it is not actually mentioned in 544.1. That is: only extraneous-conductive-parts require (main) bonding 411.3.1.2. If it is not then ...

I agree totally. However, in talking about main equipotential bonding (which only applies to extraneous-c-ps) 544.1.2 talks about attaching main bonding to something (pipes downstream of an "insulating section or union") which cannot possibly be an extraneous-c-p - so one can hardly blame people for being confused/misled !!

Kind Regards, John

 

[EFLImpudence]

It does say 'insulating'; not 'isolating'.

Is it just to stop people bonding onto an 'insulated' pipe, i.e the orange stuff.

I don't know; either way it is hardly necessary.

 

[JohnW2]

It does say 'insulating'; not 'isolating'.

Hmmmm. It does say 'insulating', rather than 'insulated'. I really think nearly everyone will read that to be talking about an 'insulating section or union' which does not maintain electrical continuity (i.e., I suppose, 'isolating' in terms of what you've said). If, as I'm sure will be the case for many/most readers, one believes that is what it is saying, then one is being told to apply main bonding to something that cannot possibly be an extraneous-c-p.

Kind Regards, John

 

[EFLImpudence]

I agree but if you distinguish between 'insulating' and ' insulated' then what is it insulating from what?

Would a plastic joint be said to be 'insulating' a pipe or one pipe from another?
If you wanted to 'insulate' all the pipework then it would be the insulation which was doing the 'insulating' and the pipes which would be 'insulated' but still connected.

As I said - either way it is not necessary (to say anything).

 

[JohnW2]

I agree but if you distinguish between 'insulating' and ' insulated' then what is it insulating from what?

I thought that by 'insulated', you were simply referring to a metal pipe that has some sort of plastic covering/'sleeving' over it.

Would a plastic joint be said to be 'insulating' a pipe or one pipe from another?

Provided it wasn't one of those plastic joints which 'helpfully' included provision for maintaining electrical continuity then I would say that it was insulating/isolating one pipe from the other. I feel sure that that (together with a section of plastic pipe) is what most readers would think the reg is talking about.

As I said - either way it is not necessary (to say anything).

Quite but, as I've suggested, I think the worst thing is that the wording of that reg helps to perpetuate the myth/misunderstanding that there are situations in which something which is not an extraneous-c-p may need to be main bonded.

Kind Regards, John

 

[flyingsparks]

Perhaps the question should be put to the technical department of my scheme..

 

[EFLImpudence]

I agree but if you distinguish between 'insulating' and ' insulated' then what is it insulating from what?

I thought that by 'insulated', you were simply referring to a metal pipe that has some sort of plastic covering/'sleeving' over it.

I was but I thought you disagreed and thought it meant a piece of plastic in the pipe run.

 

[EFLImpudence]

Perhaps the question should be put to the technical department of my scheme..

Oh I suspect that would lead to more questions.

Whatever it means, if the pipe is not extraneous it does not require bonding.

 

[JohnW2]

Whatever it means, if the pipe is not extraneous it does not require bonding.

Indeed - but the reg implies otherwise, which is probably part of the reason for all the confusion/misunderstandings.

Kind Regards, John