New CU and meter tails etc

[rajshar]

Hi
I don't know if I should ask it here or the main electricians forum. It's about CU change and the work around it and the CU change will be done by a proper registered electrician.

I will try to upload the pictures so you can see what I am talking about. I took two quotations. One just ask for pictures and quoted me for new BG CU with RCBOs, meter tails, upgrade the earth cable as the old one is only 6mm.

The second one visited my house today and after looking at the meter fuse board gave me two quotes, one including materials and one just his labour, testing and certificate charges. He said there is no need to tell Building control as he is registered and his certificate covered it. His quote includes fitting new CU and meter tails. But he said he won't change the earth cable as that is coming out of cut out and he isn't allowed to touch that. He also told me that the tails from the cutout to the meter and then to the fuse board are 16mm. The cutout fuse is rated 100A. The length of tails from cutout to meter is about 60cm and from meter to the fuse board is about 120cm including all the bends. Is all this acceptable? I know that I can ask him to fit 25mm tails to the CU but who is responsible to change the tails from cutout to the meter and who is supposed to change the earth cable for bonding from cut out to the gas pipe.

I have an appointment scheduled with British Gas to fit an isolator between the meter and fuse board as the first electrician asked for it. Can British Gas electrician change the tails and earth bonding cable from cutout while fitting the isolator?
Sorry for a long description and questions.
Thanks

 

[Midwest]

You are right, it does create doubt in mind that's why I said that I am not satisfied by his response.

Right now as I have time, I'll surely take another opinion. I know everyone works differently and that's not a problem. It's just that I have taken two quotes and none of them mentions any testing prior to installation. I spoke with my colleague and even he said that pre install testing should be done because RCDs/MCBs are more sensitive and if there is any fault, they will become nightmare. Wired fuses are more forgiving but do increase the risk, so definitely need the upgrade. If no fault then perfect otherwise it will be an opportunity to put things right.

Btw which test is carried out to determine if bonding is required when there is no extraneous conductor.

I want to prepare myself with the right questions to ask this time.
Thanks

Most CU changes don’t warrant an EICR beforehand. When I did CU replacements, I tested all the circuits before the old CU came off the wall. That was part of my pricing for the CU replacement.

IMO an EICR (before a CU change) is only necessary with a large property, or one where there is concern over of the condition of the installation. For example, I’ve had to replace the CU in my house, which is just over two years old. It would of been completely unnecessary to carry out a EICR beforehand, if I had been paying someone to do it.

 

[DPG]

The guy who told you he would take the RCBO out and replace it with an MCB if it kept tripping - you don't want him doing any electrical work in your house if that is his outlook on things.

Also, I would recommend having an SPD. Makes sense to have one now while the work is being done. Cost is minimal and it seems wise to be on the safe side. Never assume equipment is immune to surges and spikes. A company i know of once removed surge protection devices on some of its products, and guess what happened to the returns figures?

And it's not just lightning strikes that cause these spikes.

 

[nicebutdim]

Most CU changes don’t warrant an EICR beforehand. When I did CU replacements, I tested all the circuits before the old CU came off the wall. That was part of my pricing for the CU replacement.

IMO an EICR (before a CU change) is only necessary with a large property, or one where there is concern over of the condition of the installation. For example, I’ve had to replace the CU in my house, which is just over two years old. It would of been completely unnecessary to carry out a EICR beforehand, if I had been paying someone to do it.

If you were replacing a BS3036 board like that in the OP's images, rather than something of recent vintage, how might you approach the task?

 

[Midwest]

If you were replacing a BS3036 board like that in the OP's images, rather than something of recent vintage, how might you approach the task?

I would go to the house and have a look to the installation

 

[rajshar]

I found shortcomings from both electricians, so I am not going ahead with any one of them.

One was the attitude to replace RCBO with MCB if fault can't be rectified, instead he should have said that we must rectify the fault as that can be dangerous.

The second one is the earth bonding. When I told him that the supply pipes are plastic up to the house boundary he said he will leave the water pipe but he will upgrade the bonding to gas pipe anyway.

Strima said that you guys will calculate in this scenario if bonding is required. I read about bonding in the following article.

https://electrical.------.org/wiring-matters/years/2018/73-november-2018/myth-busters-2/

So it certainly makes a case to do proper assessment and calculation and then bond if required. So that is another thing

I will take few more quotes now because now I know what should I ask. I am fairly sure that old cables and sockets(MK brand) are in very good condition. The only sockets which I have doubt are relatively new ones fitted in the kitchen during kitchen refit about 9 years ago. They are of Lap. One was causing sparks during on/off and blew the fuse. I have changed 3 single Gang sockets with Schneider sockets. I will replace the other sockets in the kitchen too. Is Schneider fine or should I get the MK brand sockets.
May be I should just get an EICR first and if there is a need for rewire then sort that first at the first opportunity and then at the same time do the CU upgrade. If no faults then just do the CU upgrade. The new circuit in the kitchen can wait until that time.

Btw, a lot of you are emphasising on SPDs. I am still not convinced of their benefit in an average city house. Anyway if one has to go with SPD then is it allowed to mix different brands in a CU or not. I know you can't mix different brands RCD/RCBO/MCBs. Whatever make is the CU, it should be the same make components. So is it same for SPDs. I am asking this because there is huge difference on price of SPDs between different Makes?
Should I also go with AFDD as that provide additional protection too?
Thanks for all your help

 

[DPG]

I found shortcomings from both electricians, so I am not going ahead with any one of them.

One was the attitude to replace RCBO with MCB if fault can't be rectified, instead he should have said that we must rectify the fault as that can be dangerous.

The second one is the earth bonding. When I told him that the supply pipes are plastic up to the house boundary he said he will leave the water pipe but he will upgrade the bonding to gas pipe anyway.

Strima said that you guys will calculate in this scenario if bonding is required. I read about bonding in the following article.

https://electrical.electriciansforums.org/wiring-matters/years/2018/73-november-2018/myth-busters-2/

So it certainly makes a case to do proper assessment and calculation and then bond if required. So that is another thing

I will take few more quotes now because now I know what should I ask. I am fairly sure that old cables and sockets(MK brand) are in very good condition. The only sockets which I have doubt are relatively new ones fitted in the kitchen during kitchen refit about 9 years ago. They are of Lap. One was causing sparks during on/off and blew the fuse. I have changed 3 single Gang sockets with Schneider sockets. I will replace the other sockets in the kitchen too. Is Schneider fine or should I get the MK brand sockets.
May be I should just get an EICR first and if there is a need for rewire then sort that first at the first opportunity and then at the same time do the CU upgrade. If no faults then just do the CU upgrade. The new circuit in the kitchen can wait until that time.

Btw, a lot of you are emphasising on SPDs. I am still not convinced of their benefit in an average city house. Anyway if one has to go with SPD then is it allowed to mix different brands in a CU or not. I know you can't mix different brands RCD/RCBO/MCBs. Whatever make is the CU, it should be the same make components. So is it same for SPDs. I am asking this because there is huge difference on price of SPDs between different Makes?
Should I also go with AFDD as that provide additional protection too?
Thanks for all your help

If you are quibbling about the cost of installing SPDs then the price of AFDDs will blow your mind!

AFDDs are more of an unproven and unknown quantity. SPD technology has been around for a hell of a long time and it is well understood.

Don't waste time trying to mix and match manufacturers - you can get a full RCBO board with SPD included for not a lot of money. Check out 'Fusebox' as one make that people seem pretty positive about.

 

[pc1966]

Is Schneider fine or should I get the MK brand sockets.

Both are good but NOT the MK "essentials" range, they are utter rubbish and not even cheap enough to justify them!

My own choice has bee the MK Logic Plus range as they are sufficiently bland smooth white appearance not to seem out of place in most situations, and still have a pleasing feel/action/quality for a fair price. Also the switched Logic Plus 13A sockets are double-pole switches, not all are as the minimum requirement is SP switching when present.

Others on this forum will have favourites as well, but do chose one of the better brands as it is worth the odd quid extra per accessory.

 

[littlespark]

I’ve read right through this thread, and I have to concur with some of the points regarding rcd protection.

changing a board means having to work on every circuit, and protect with an rcd if required.... and newest regs require almost every circuit to be rcd protected.

To suggest replace an rcbo with an mcb is the modern equivalent of replacing a fuse with a nail to stop it blowing

I might be wrong here, but would your gas pipe be plastic coated copper rather than just plastic? Meaning it will need bonded.
Water pipe could well be plastic though.

 

[rajshar]

I don't know which MK type sockets we have. I just know that in the middle of the faceplate there is MK in a circle. I will look at the MK logic plus range.

I don't know about fuse box for SPD but looked at Wylex and that adds £75 more for SPD. The BG SPD is about £38 but a lot of people say don't go with BG. How is Fusebox in comparison to Wylex and Hager. The CU box itself is just a metal box and I don't think there is much difference between the different makes other than the cut outs etc. The actual difference is in the components going inside the CU.

I really don't get that why SPDs weren't made compulsory? Why majority of consumer boards being sold, don't have one?
The other point is about type A and AC RCD)RCBOs. There is no difference in price and type A offers better protection as it can deal with residual DC and still a lot of sellers are selling pre populated CU with type AC RCD/RCBOs. I even heard that a few European countries actually have banned type AC RCD/RCBOs.
One hand I am better off having the knowledge now and on the other hand a lot of questions in mind, why this, why not that and then I think I was better off when I didn't have this knowledge.
Thanks

 

[brianmoooore]

I might be wrong here, but would your gas pipe be plastic coated copper rather than just plastic? Meaning it will need bonded

There's also the point that no one seems to have told the average gas 'engineer' that plastic pipes don't need bonding, so it's sometimes easier to bond than to argue with the gas man.

 

[rajshar]

I’ve read right through this thread, and I have to concur with some of the points regarding rcd protection.

changing a board means having to work on every circuit, and protect with an rcd if required.... and newest regs require almost every circuit to be rcd protected.

To suggest replace an rcbo with an mcb is the modern equivalent of replacing a fuse with a nail to stop it blowing

I might be wrong here, but would your gas pipe be plastic coated copper rather than just plastic? Meaning it will need bonded.
Water pipe could well be plastic though.

I know that changing to MCB without RCD isn't the right thing as it takes away the protection which we are trying to get. For me then there isn't any point upgrading from wylex plug in mcbs to slightly different type of MCB. So no we won't do that.

Inside the house the water and gas, both are copper. Outside it is plastic . The plastic gas pipe was inserted in the existing metal pipe from the street. The same with water pipe. It is about few foot in plastic from the meter and then connects to a flexible lead pipe, going in to the house. The lead pipe is then connected to a copper pipe under the kitchen floor boards.

There is only about 2 meters of visible gas pipe, where the meter is, rest is all hidden. As far as water pipe is concerned, no visible part in kitchen. The visible water pipe in the bathroom is copper but under the floor boards it was changed to plastic some 10 years back so there is no continuity to the main water pipe.
Thanks

 

[brianmoooore]

If you still have a section of lead water pipe in use, I would get that replaced ASAP.

 

[rajshar]

If you still have a section of lead water pipe in use, I would get that replaced ASAP.

It's definitely lead pipe from outside into kitchen under floor. I remember seeing it when kitchen was fitted. Thames water should have known this as well when they changed to plastic pipe. Its about an inch in diameter and one can bend it easily.

No one ever said it should be replaced and now if we try to do it is going to cost thousands. Tiled floor in the kitchen, laminate in the hallway then the stairs in to the house and then the drive. Dig up, change the pipe then put back everything back to its original position.

Btw why it should be changed. Are there any health issues? Do you know if there were any guidance or instructions issued? I understand that I am responsible for the water pipe from the street boundary to my house so Thames water won't do it.
Thanks

 

[brianmoooore]

It doesn't necessarily need to follow the same route, or end up at the same place inside. I obviously don't know the specifics of your house, but there's often an alternative route.

 

[DPG]

It's definitely lead pipe from outside into kitchen under floor. I remember seeing it when kitchen was fitted. Thames water should have known this as well when they changed to plastic pipe. Its about an inch in diameter and one can bend it easily.

No one ever said it should be replaced and now if we try to do it is going to cost thousands. Tiled floor in the kitchen, laminate in the hallway then the stairs in to the house and then the drive. Dig up, change the pipe then put back everything back to its original position.

Btw why it should be changed. Are there any health issues? Do you know if there were any guidance or instructions issued? I understand that I am responsible for the water pipe from the street boundary to my house so Thames water won't do it.
Thanks

Makes sense to remove the lead pipe due to the obvious health risks it poses.

Having said that my Nan's house had lead piping all the way up the drive, through the yard and throughout the house and she lived to be 100.