Need to add a socket, advice please?

[KnightWhoSaysNi]

One of the bedrooms has a cupboard with a combi gas boiler.
The boiler is connected to the mains via an isolation switch, which is mounted on the wall inside the cupboard.

I've bought a somewhat bulky wireless printer and thought the cupboard would make a good house for it. As there are no sockets in there, I'd have to fit one.

I have a socket, a surface mounting box, isolation tape and plenty of cable. I've heard terms such as ring, radial circuit and spur, but I'm not sure what they mean and what I need here. Can someone please advise on how to wire it, in terms of what wire connects to what, and whether I need to buy anything else (fuses for example...?)

I might use the socket for other purposes than the printer, but they'd all be low-wattage.

 

[Taylortwocities]

Your first job is to find out if the feed to the isolation switch is on a ring final, or a radial circuit.

A photo of the wiring to the back would be useful.

PS, does the boiler isolation switch have its own fuse?

 

[stillp]

You could start by reading some of the Wiki at //www.diynot.com/wiki/Electrics:index

 

[KnightWhoSaysNi]

Your first job is to find out if the feed to the isolation switch is on a ring final, or a radial circuit.

A photo of the wiring to the back would be useful.

PS, does the boiler isolation switch have its own fuse?

Here is a photo:

The boiler is on its own circuit according to the card on the fuse box (although there are 2 cables coming out of that slot).

The isolation switch does have its own fuse.

You could start by reading some of the Wiki at //www.diynot.com/wiki/Electrics:index

Thanks, will do.

 

[Taylortwocities]

The boiler is on its own circuit according to the card on the fuse box (although there are 2 cables coming out of that slot).

The isolation switch does have its own fuse.

Next questions, then.
1. What is the value (in Amps) of the fuse or MCB that is protecting the "boiler" circuit.
2. Can you post a photo of your fusebox as new sockets need a special type of protection, called an RCD, need to know if you have one.
3. It sounds like something else is also powered by the "boiler circuit" if there are 2 cables attached to the fuse in the fuse board. What also stops working if you turn off that MCB/remove the fuse of the "boiler circuit".

I am trying to determine if you could just hang another socket off the back of the boiler isolator switch, or if you need to other things too.

 

[ban-all-sheds]

One of the bedrooms has a cupboard with a combi gas boiler.

I hope you have a good CO detector in there.

I've bought a somewhat bulky wireless printer and thought the cupboard would make a good house for it.

How warm does it get inside the cupboard?

Will you be able to hear any alarms from the printer for faults?

Have you checked, by using an extension lead, that you get a reliable wireless connection in there, with all boiler operating modes?

I have a socket, a surface mounting box, isolation tape and plenty of cable.

You won't need the tape.

What sort of cable?

 

[KnightWhoSaysNi]

Next questions, then.
1. What is the value (in Amps) of the fuse or MCB that is protecting the "boiler" circuit.

16 Amps

Can you post a photo of your fusebox as new sockets need a special type of protection, called an RCD, need to know if you have one.

3. It sounds like something else is also powered by the "boiler circuit" if there are 2 cables attached to the fuse in the fuse board. What also stops working if you turn off that MCB/remove the fuse of the "boiler circuit".

I haven't found anything that would stop working beside the boiler. It's possible that the other cable is not in use anymore (?).

I hope you have a good CO detector in there.

I have a battery-operated British Gas detector.

How warm does it get inside the cupboard?

The cupboard has grille vents, one at the top and one at the bottom. It doesn't really get hot in there, maybe just 3C above the room temperature.

Will you be able to hear any alarms from the printer for faults?

If I'm in that room - I think so.

Have you checked, by using an extension lead, that you get a reliable wireless connection in there, with all boiler operating modes?

On my smartphone - yes. I'm collecting the printer tomorrow.

What sort of cable?

I have 2 cables, one 1.5 mm2, the other 4 mm2. Both are Twin & Earth.

 

[PBC_1966]

That RCD is not the right sort for sockets - they need a 30mA trip.

Looking at the age of that unit, 100mA would have been the accepted norm at the time it was installed, and then probably only for sockets which might be expected to feed equipment used outdoors, even though in this case it's protecting the whole house. Somewhat unusual to have a 16A MCB for lighting though.

 

[Taylortwocities]

Given the age of the fuse board (and the installation), I will bet that the "boiler circuit" was originally a feed for an immersion heater. Perhaps that is why the boiler (combo?) is in teh bedroom - in teh old hot water tank cupboard.

So, back to the matter in hand.
You will need two things. A length of cable - you could use the 4mm, but it may be too big for the terminals. The 1.5mm² is just (but only just) within spec. For me I would use a length of 2.5mm².

You need to connect to the L,N and E of the FEED terminals on teh boiler isolation switch.

You will need an RCD protected socket. The RCD in your fuseboard is 100mA trip and that's not correct. Sockets must be protected by a 30mA RCD.
One of these will do you.

Thats all you need.

 

[JohnD]

One of these will do you.

eh?

 

[Iggifer]

i think that link may have been supposed to be something like this

 

[KnightWhoSaysNi]

Thanks TTC. I got the link right - https://www.tlc-direct.co.uk/Products/KBRCD9000.html? - you need to copy and paste it, because the forum software is messing with links.

If I understand correctly, your suggestion to get an RCD socket doesn't just apply specifically to this particular socket, but all sockets in my house. So if I want to comply with the new standards, I'd have to replace them all (and I have like 15 of them)? Isn't there a simpler and cheaper way around this?

And if I don't care about complying, I can as well use a standard socket here. It would be unsafe, but having one safe socket doesn't make the house safer if the other 15 sockets are unsafe anyway. Is my understanding correct?

@srhawksy: it's a condensation combi boiler.

 

[ban-all-sheds]

Looking at the age of that unit, 100mA would have been the accepted norm at the time it was installed,

That was then.

This is now.

and then probably only for sockets which might be expected to feed equipment used outdoors

That was then.

This is now.

 

[ban-all-sheds]

If I understand correctly, your suggestion to get an RCD socket doesn't just apply specifically to this particular socket, but all sockets in my house. So if I want to comply with the new standards, I'd have to replace them all (and I have like 15 of them)? Isn't there a simpler and cheaper way around this?

You are not required to update what you already have. The regulations on the type of RCD protection required for sockets only apply to new ones.

 

[PBC_1966]

So if I want to comply with the new standards, I'd have to replace them all (and I have like 15 of them)?

If you wanted to bring the entire house up to the current standard of BS7671 there are quite likely numerous other things you would need to change as well, but that would be getting carried away just to add one socket.

Isn't there a simpler and cheaper way around this?

Yes......

And if I don't care about complying, I can as well use a standard socket here. It would be unsafe, but having one safe socket doesn't make the house safer if the other 15 sockets are unsafe anyway. Is my understanding correct?

It wouldn't be unsafe, and would be just as safe as all the other sockets in the house at the moment. Even if you wanted to comply with the current edition of BS7671, that would not require you to change all the other sockets to 30mA RCD protection, only to provide it for the new one. There must still be hundreds of thousands of homes across the U.K. which have no RCD protection on sockets whatsoever; while adding RCD protection might add a level of safety, that doesn't mean that they're unsafe without it. You already have a higher degree of RCD protection through that main 100mA device than those.