Kitchen sockets

[dannydc]

Hi All

I'm putting a new kitchen in at my mum's house and have a couple of electrics questions:

1. There is an old unused FCU for an immersion heater that must have been removed when the combi boiler was installed. The wire looks like maybe 2.5mm² or 4mm² and has one leg that goes upstairs to the airing cupboard where the immersion heater would have been, and one leg that ends next to the fuse box (unconnected). Is there any reason why we couldn't get an electrician in to connect that wire up to the fuse box and use it for the oven? That would leave the leg that goes upstairs disconnected which is fine.

2. I want to add some sockets in the kitchen. The kitchen is currently supplied by an existing 2-gang socket on the ring main, plus a spur of two more 2-gang sockets. Can I just extend that spur with 2.5mm² cable, connecting into one socket and out to the next? I want to add one more 2-gang, and two 1-gang sockets (for general use, the hob sparker and the overhead extractor fan).

Rather than wiring from one socket to the next, could I do a star arrangement from a junction box to the end three sockets instead? I presume not, but I'm not sure why it would be a problem, other than perhaps for testing the circuit's resistance?

The total length of the spur is probably 6m, and the ring main is probably 5m in either direction back to the fuse box - it's not a huge house. The spur won't be for the oven, washer, dishwasher or microwave - that stuff is all elsewhere on the ring main.

3. Can the last leg of the spur be in 1.5mm² cable? That's already installed and although it's in conduit I'd rather not have to pull it out and re-do it. It's for the cooker extractor fan.

4. Can the cables be surface mounted behind the units? They're running vertically down the wall in chased out conduits, but under the units do they have to be in conduits or is surface mount ok? I can't fit conduit behind the units so it would have to go on the skirting board below.

Thanks!
Danny

 

[flameport]

1. Probably, although the effort is hardly worthwhile just to use a bit of old cable worth approximately nothing.

2. What you have now is not compliant, and therefore must be changed. You certainly can't add anything to it.

As the entire kitchen is being replaced, this is the ideal and only time to forget about whatever defective old wiring is there, and put in a new circuit for sockets and other items.

 

[ban-all-sheds]

3. Danny - I have no idea, given the mix of "can I do" and "can I get someone to do" questions whether you will be using an electrician or not.

Are you able to clarify?

 

[dannydc]

3. Danny - I have no idea, given the mix of "can I do" and "can I get someone to do" questions whether you will be using an electrician or not.

Are you able to clarify?

I'll do whatever I can legally/safely. I'd get someone in to connect up to the fuse box though.

 

[ban-all-sheds]

Are you going to expect that someone to give you a certificate?

What are you going to do about Building Regulations approval?

 

[dannydc]

My understanding is that I can do the work myself, except for #1 because that's installation of a new circuit and so needs to be done by someone who is certified as MTC:

https://www.gov.uk/government/uploa...ata/file/294483/3rd_Party_Cert_Scheme_MTC.pdf

https://www.gov.uk/building-regulations-approval/when-you-dont-need-approval

Otherwise, it's not in a "Special Location" (i.e. a bathroom) so I don't think I need someone who is MTC or to inform building control. Can anyone confirm?

 

[flameport]

If it was notifiable as in new circuit, you can either notify and do everything yourself, or get an electrician to do everything and notify.

However as you already have a ring supplying sockets in the kitchen, nothing is notifiable.
You find the two ends of the ring entering the kitchen, connect all of your new sockets between those ends (therefore extending the ring), and remove any other old wiring that might happen to be there.

You then have a new kitchen will all new wiring, sockets and other connections exactly where you want them, and don't have to rip out half the kitchen in a few months or years to locate some fault on the old bodged wiring.

 

[JohnW2]

If it was notifiable as in new circuit, you can either notify and do everything yourself, or get an electrician to do everything and notify.

... or, per the OP's link, utilise a Third-Parter Certifier (if one can find one) - but that person would then have to be involved before the work started.

Kind Regards, John

 

[deadshort]

1. Probably, although the effort is hardly worthwhile just to use a bit of old cable worth approximately nothing.

2. What you have now is not compliant, and therefore must be changed. You certainly can't add anything to it.

As the entire kitchen is being replaced, this is the ideal and only time to forget about whatever defective old wiring is there, and put in a new circuit for sockets and other items.

This is the best advice you have been given, install a new circuits as required. If funds are tight do all the prep work and have your electrician check their happy with the first fix before you pay them to wire and connect.

Regards,

DS

 

[dannydc]

1. Probably, although the effort is hardly worthwhile just to use a bit of old cable worth approximately nothing.

2. What you have now is not compliant, and therefore must be changed. You certainly can't add anything to it.

As the entire kitchen is being replaced, this is the ideal and only time to forget about whatever defective old wiring is there, and put in a new circuit for sockets and other items.

This is the best advice you have been given, install a new circuits as required. If funds are tight do all the prep work and have your electrician check their happy with the first fix before you pay them to wire and connect.

Regards,

DS

Thanks for the advice everyone.

I'm a bit confused! First, I wasn't clear why I want to re-use the immersion heater cable from the fuse-box to the old FCU - that cable is chased in through the dining room and under the upstairs floor over to the fuse box, so re-using that existing cable would save a lot of work over installing a new cable to the oven.

Second, I don't understand why the circuit as it currently is (ring-main to a spur containing 2x 2-gang sockets, - the spur of which was installed by a certified electrician - the ring main was already there when we bought the hosue) isn't compliant?

 

[flameport]

A spur from a ring can only have one socket outlet on it - you already have 2 which is not compliant, adding more would make this worse.

The only way to have more than one socket on a spur from a ring is to put a 13A fuse at the start of the spur, but this would be totally useless for a kitchen.

Cables are generally clipped to the wall behind the units just below the worktop level, with a short chase up to each socket outlet.

 

[dannydc]

A spur from a ring can only have one socket outlet on it - you already have 2 which is not compliant, adding more would make this worse.

The only way to have more than one socket on a spur from a ring is to put a 13A fuse at the start of the spur, but this would be totally useless for a kitchen.

Cables are generally clipped to the wall behind the units just below the worktop level, with a short chase up to each socket outlet.

Brilliant - thanks, this fills in the blanks that I was missing. So I can do the kitchen circuit as I was expecting, except I need to connect the far end of it back to the ring-main and break the ring so as to avoid creating a figure-8 circuit which I believe would be non-compliant due to difficulties with testing it.

I'll make sure my mum doesn't use the electrician who replaced one of the two sockets on the spur seeing as it's a non-compliant set-up.

Thanks all
Danny

 

[PrenticeBoyofDerry]

1. Is there any reason why we couldn't get an electrician in to connect that wire up to the fuse box and use it for the oven? That would leave the leg that goes upstairs disconnected which is fine.

A good reason not connect it would be if it was not safe or fit for continued safety, would be best just to run a new suitable cable in for the oven, it maybe that a higher rated cable would be required anyway.

2. I want to add some sockets in the kitchen. The kitchen is currently supplied by an existing 2-gang socket on the ring main, plus a spur of two more 2-gang sockets. Can I just extend that spur with 2.5mm² cable, connecting into one socket and out to the next? I want to add one more 2-gang, and two 1-gang sockets (for general use, the hob sparker and the overhead extractor fan).

You cannot add spurs to spurs on ring final circuit, only one socket outlet can directly spurred from a socket on the ring, unless the original spur is via a 13A fused connection unit. Also any new cable that is buried in walls and any new socket, will require 30mA RCD protection, if this circuit is not already protected by this.

Rather than wiring from one socket to the next, could I do a star arrangement from a junction box to the end three sockets instead? I presume not, but I'm not sure why it would be a problem, other than perhaps for testing the circuit's resistance?

If you can avoid junction boxes do so, if not you will very likely require to us MF (maintenance free) ones.

3. Can the last leg of the spur be in 1.5mm² cable? That's already installed and although it's in conduit I'd rather not have to pull it out and re-do it. It's for the cooker extractor fan.

You could spur in 1.5mm2 providing it was down fused.

4. Can the cables be surface mounted behind the units? They're running vertically down the wall in chased out conduits, but under the units do they have to be in conduits or is surface mount ok? I can't fit conduit behind the units so it would have to go on the skirting board below.

They can be surfaced mounted in trunking/conduit or clipped direct to the surface. The cable requires to be fixed/supported securely and placed in a postion where it is not going to be accidentally damaged.