When does a Consumer Unit Require an update? Confused.

[dishman]

Just getting a quote for some minor work to a property. During discussion with the electrician, he said the consumer unit would need updating to meet modern standards.

The work consists of the swapping of some single sockets to doubles (maybe adding one or two). Changing of a pendant light to a number of spotlights in the kitchen. The moving and addition of some light switches. The addition of an extractor fan with isolation switch. The loft could also do with it's own feed from the main consumer unit. The sockets and lights are not RCD protected. It has its own fuse box up there, like a detached garage.

The existing consumer unit has a single RCD protection o half the circuts (early 90's). I have no issue with upgrading it if required for safety etc. But, I have read a few times on the forum that "if the installation met the standards of the day" then an upgrade is not required. Some people, after reading posts on the forum (yes, I used the search function!) have suggested that an electrician who makes this case may be pulling a fast one.

I did ask the electrician why an update would be required and the response was that due to the nature of the work, changing current circuit layouts with cabling embedded in the walls, an upgrade would be required.

So for clarity, what kind of work on a property triggers the requirement of the consumer unit to be updated?

Thanks in advance.

 

[EFLImpudence]

The answer, really, is never.

However, if new fittings require features the present CU cannot incorporate then it may be cheaper to fit a new one.

You say yours has one RCD so it can't be that old so may be possible to just fit your new requirements without replacement.

 

[dishman]

hmmm, that is not how he put it.

As far as I can see, no new circuits need to be added. It is just as I said, changing existing ones i.e lighting from pendant to multiple spots. Adding a switch here and there. Even adding the main feed to the loft should not be an issue as I want the electric shower removed (which is rcd protected). He suggested that this could be used to power the ring in the loft instead (which I hoped was an option). That is the only major change.

I asked the question directly and he as per above he suggested it was due to the fact he was working on a lighting circuit that was not RCD protected, meant he had to make it RCD protected to comply.

 

[EFLImpudence]

As far as I can see, no new circuits need to be added. It is just as I said, changing existing ones i.e lighting from pendant to multiple spots. Adding a switch here and there.

Nothing there to warrant new CU.
Some new cables may have to be RCD protected but you have one RCD.

Even adding the main feed to the loft should not be an issue as I want the electric shower removed (which is rcd protected). He suggested that this could be used to power the ring in the loft instead (which I hoped was an option). That is the only major change.

Yes, you won't need a ring in the loft but that's nothing to do with the CU.

I asked the question directly and he as per above he suggested it was due to the fact he was working on a lighting circuit that was not RCD protected, meant he had to make it RCD protected to comply.

That's true.

Have you room for a second RCD - i.e. two spare ways?
If not then one or more RCBOs (RCD and MCB combined in one) only as wide as an MCB - could be fitted.

 

[EFLImpudence]

Also, if anyone says you need to have it replaced just because it is not metal then get a new electrician.

 

[EFLImpudence]

I suppose your CU could be one of the earliest with an RCD so may be obsolete.

Post a picture - just copy and paste or drag to reply box.

 

[dishman]

He did mention the metal consumer unit being another reason to update, but as an aside to the other reasons. I could not be sure if he was saying that made it a requirement to update, but he was close to it. It was more of an "it is another reason to..."

None of the lighting circuits are RCD protected and, as you can see, there is no space to add one. So I guess this could be the main catalyst for him to suggest it required a new consumer unit.

The heating circuit currently links to the consumer unit (well fuse box) in the loft. Ideally this would be swapped with the shower and put back to use as a backup immersion.

 

[plugwash]

The regs are not very clear on to what extent an existing installation needs to be upgraded during extension/modification work.

However a common interpretation is that any new stuff must be installed to current regs. In particular this is an issue because the 17th edition regs require regular sockets to be RCD protected and require concealed cables to be either RCD protected or installed in a special way. In some cases replacing the CU can be the best way to deal with a lack of RCD protection.

However having seen the photo of your CU I don't think yours is one of those cases. The sockets are RCD protected already and I belive compatible RCBOs for the wylex NSB range are still made, so you can RCD protect the lighting circuits by replacing the MCBs with RCBOs.

Another possible reason to replace a CU would be lack of space. You say the loft has it's own fuse box but you don't say where that fuse box is fed from and I don't see any evidence of a breaker feeding it in your current CU.

 

[dishman]

Another possible reason to replace a CU would be lack of space. You say the loft has it's own fuse box but you don't say where that fuse box is fed from and I don't see any evidence of a breaker feeding it in your current CU.

As per above, maybe I was not clear. The heating breaker was re-purposed to power the fuse box in the loft. It was just not re-labelled.

 

[EFLImpudence]

Yes you can get RCBOs to fit that one.

A bit of reconfiguring and/or a more modern RCD would make space as well as the three half-size blank spaces.

 

[deadshort]

Can you ?

DS

 

[dishman]

So, the question is.

Is it more appropriate to fit some RCBOs and have the option of making space or replace the whole CU.

What would the cost difference between the two be?

And should the electrician given me that option?

 

[EFLImpudence]

Can you ?

According to TLC.

https://www.tlc-direct.co.uk/Manufacturers/Wylex/Wylex_Ns_2/index.html

 

[PrenticeBoyofDerry]

To comply to regulations, any new sockets and cable newly buried less than 50mm (including reverse side of wall) in walls that are not mechanically protected on existing circuits, will very likely require RCD protection.

Whether that constitutes the installation of new board, would be a judgement call on the likely cost, any inconvenience and compliance without the need for a new RCD protected board!

 

[PrenticeBoyofDerry]

So, the question is.

Is it more appropriate to fit some RCBOs and have the option of making space or replace the whole CU.

What would the cost difference between the two be?

And should the electrician given me that option?

The choice is yours and the electrician should have advised you so.