New Consumer Unit

[uksparks]

Hi,

I have a consumer unit to change, the earth on the gas is easy enough but the water is in 6mm and literally the other end of the house and would be a nightmare running in a new cable.

Would you be happy changing it and leaving a 6mm in? Im going on Tuesday to do some pre work tests etc so can have another look.

Ill be quite honest, in all the consumer unit changes I have done, I have always updated the earth to 10mm as its never been an issue, but this is the first one where its going to be a complete pain in the --- doing it.

Whats your thoughts?

 

[uksparks]

Just to add, it is green and yellow, so not like its just green.

 

[Leesparkykent]

What's the earthing arrangement?

 

[VoltzElectrical]

If it was good enough for previous editions of the regs....

 

[uksparks]

I 'think' if i remember correcly it was TNS.

 

[uksparks]

Like I say, I always update it, but never had this predicament before, quite honestly its never going to be a problem, more chance of the commet in 2022 hitting earth.

 

[Octopus]

I looked at one today where running a cable from the CU to the incoming water would mean going round most of the house, yet behind the wall from the CU is the cloakroom with a nice copper water pipe - makes me think that sometimes thinking outside the box is sensible!

 

[uksparks]

Tell a lie, Ive just found a picture and it looks like its PME not TNS.

 

[uksparks]

Unfortunately this is a mid terrace, quite an old property, probably 1930 I think, no access either side due to neighboring houses.

Its kind of a non starter, plus the bathroom and kitchen are both downstairs at the back of the house which is quite deep front to back and no water at all in the rest of the house, so would literally have to go from front to back and probably trash half the house in the process.

 

[Leesparkykent]

I 'think' if i remember correcly it was TNS.

IMO it's happy days as long as no sign of mechanical/thermal damage on the 6mm. But if there is a cold water supply nearer the DB like a downstairs WC or the like and wouldn't be to much disruption I would still bang in a 10mm and mark it down on the cert that the new MEB to water is not within 600mm of the water stopcock but existing 6mm is.

 

[Des 56]

Perhaps its best to keep in mind the reason for the bond
Dumping it where it happens to suit may not achieve what it is installed in the first place to provide

If you do leave the 6mm in situ,there is guidance on the Esc site regards this matter

 

[TJ Anderson]

Like I say, I always update it, but never had this predicament before, quite honestly its never going to be a problem, more chance of the commet in 2022 hitting earth.

You are right it won't be a problem. I would just note on EIC, 6mm Main Protective Bonding Conductor - No signs of thermal damage. Also your Gas is in 10mm, Cross bonded to water through boiler etc. It has been fine for years like it is, and you are leaving installation safer than you left it by adding RCD protection. Crack on with it mate.

 

[Octopus]

Bonding BS 7671 rule 131.8 (BRB) is now 132.16 (BGB) - don't know what it is in the (BYB)

 

[Resu]

Trainee question! Would I be right in saying that although it's TN-C-S it might not necessarily be PME?

 

[Deleted member 38070]

id put a 10mm in, even if i had to go into roof space and back (maybe 16 if that log a run) itll be worth it in the end (you know you want to ;-)

 

[uksparks]

Trainee question! Would I be right in saying that although it's TN-C-S it might not necessarily be PME?

True, but I think if you ring WPD they will say all TNC-S is now PME, I just call it the same, because it generally is as far as I am concerned.

 

[Resu]

True, but I think if you ring WPD they will say all TNC-S is now PME, I just call it the same, because it generally is as far as I am concerned.

Hey, I don't doubt it mate, was just an observation!

 

[Leesparkykent]

Unfortunately this is a mid terrace, quite an old property, probably 1930 I think, no access either side due to neighboring houses.

Its kind of a non starter, plus the bathroom and kitchen are both downstairs at the back of the house which is quite deep front to back and no water at all in the rest of the house, so would literally have to go from front to back and probably trash half the house in the process.

View attachment 27753

could well still be TNS even though it looks like TNC-S.

 

[davesparks]

Your average 1930's built house is going to have suspended floors downstairs and T&G floorboards both up and downstairs, so spring a few floorboards and run a 10mm bond to where you need it.

This is of course assuming you have already confirmed that bonding is actually required in the first place?

There are a lot of 1970/80's terraces and wimpey homes around here which follow the basic layout of gas and electricity by the front door and water main under the sink at the rear of the house with 6mm main bonds. The water main is however a black plastic pipe and rarely actually requires a main bond in the first place so I am normally perfectly happy leaving it as it is.

 

[7029 dave]

Looked at the pic, IMO if the 6mm bond is mech okay and no thermal damage leave it. Measure it as well for piece of mind. (you know the value you are looking for.)