Consumer Unit RCD question

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Hi all, I have a question regarding the RCD protection in my consumer unit, photo attached.

My understanding is that the MCBs in positions 1, 2, 3 and 4 are not protected by an RCD, as per the regs of the time. I would like to protect these circuits, in particular number 2, as we've recently had a bedroom converted into a bathroom and the sparks put new wiring, downlights and an extractor fan in running off the existing number 2 circuit. They also fitted a heated LED mirror cabinet with a built in shaver port, also running off the lighting circuit. It concerns me that this isn't protected by an RCD, especially as it is of metal construction and is touched daily by the whole family.

The shower circuit in position 7 is no longer used as we have switched to a boiler fed shower.

My question is, now that the electric shower is out of commission, can the CU be rejigged by moving the right hand RCD so that it protects all of the circuits to the right of it? Alternatively, would there be any be problem with rewiring the position 2 light circuit and B10 MCB into the space currently occupied in position 7?


Screenshot 2025-04-03 124931.png
 
The consumer unit could be reconfigured to achieve anything you want, but -

I would suggest the easiest option is to replace any or all of circuits 1, 2, 3, 4 with RCBOs - these are individual circuit breakers which combine RCD and MCB function.

I do not know why the labels state RCBO as there is none in your CU.
 
can the CU be rejigged by moving the right hand RCD so that it protects all of the circuits to the right of it?
The RCDs protect the circuits to the LEFT of them, not the right!
The CU has been configured as what was (I don't understand why) called a High Integrity board, which it isn't.
The CU could be reconfigured to move the right-hand RCD to the right hand side and protect all of the circuits 1 through 8, but that goes against a sensible configuration. It will also be a serious piece of work as the line busbars will need replacing and the neutral terminal blocks wont be correct.
I agree with @EFLImpudence , the easy option is to replace circuits 1 through 4 with RCBOs.
Or just the one protecting the bathroom lighting > https://www.tlc-direct.co.uk/Products/CPCBR0610AB.html
Also needs some minor changes to the consumer unit.

Would need to see the layout of your bathroom to see if RCD was actually required. If it is then the sparks should have done this work to meet regulations and should have notified the work to their CPS and therefore to Building Control.
 
Note also that the RCD's are incorrectly labelled as RCBOs!
 
The RCDs protect the circuits to the LEFT of them, not the right!
The CU has been configured as what was (I don't understand why) called a High Integrity board, which it isn't.
The CU could be reconfigured to move the right-hand RCD to the right hand side and protect all of the circuits 1 through 8, but that goes against a sensible configuration. It will also be a serious piece of work as the line busbars will need replacing and the neutral terminal blocks wont be correct.
I agree with @EFLImpudence , the easy option is to replace circuits 1 through 4 with RCBOs.
Or just the one protecting the bathroom lighting > https://www.tlc-direct.co.uk/Products/CPCBR0610AB.html
Also needs some minor changes to the consumer unit.

Would need to see the layout of your bathroom to see if RCD was actually required. If it is then the sparks should have done this work to meet regulations and should have notified the work to their CPS and therefore to Building Control.

Apologies, I should have worded it, "Can the CU be rejigged by moving the right hand RCD so that it protects all of the circuits currently to the right of it".

But it does sound so much easier to just replace MCBs 1-4 with RCBOs.

I did notice the labels incorrectly stating RCBOs myself, but it was put in many years before I bought the house so I can only wonder why.

What are the minor changes required?
 
What are the minor changes required
If you are swopping to RCBOs there may be the need to move/relocate some of the wires inside the CU. Certainly the neutral will be in the wrong place. Depends on what sort of a rats nest is in there too!
And, if course, you’d need to run the necessary tests (got an RCD tester?) and complete a minor works certificate.
 
I did notice the labels incorrectly stating RCBOs myself, but it was put in many years before I bought the house so I can only wonder why.
It's all rather odd and, as you say, one certainly has to "wonder why"!

Ironically, the label of the right-hand RCD has been changed by hand (presumably from "RCD") to "RCBO". The other odd thing is gthat (although I suppose it could well have been different at the time it was installed), these days nearly all domestic CU RCBOs are only one module wide (whereas RCDs continue to be 2-module wide), yet the left-hand one of those (printed) labels (which presumably came with the CU is 2 modules wide but says (printed) "RCBO"
What are the minor changes required?
Well, as has been hinted, if you change to RCBOs, the neutrals of the circuits will have to be connected to the RCBOs, rather than to a 'neutral bar' as at present.

Kind Regards, John
 
Would need to see the layout of your bathroom to see if RCD was actually required. If it is then the sparks should have done this work to meet regulations and should have notified the work to their CPS and therefore to Building Control.

This is something that crossed my mind. I didn't commission the sparks myself, rather they were subcontracted by the bathroom installers, and while they did appear to be a legitimate, established local firm, I wasn't impressed when they wired the fan switched live only and didn't bother asking me if I wanted the timer over-run activating, which is an absolute no-brainer in a steamy bathroom as far as I'm concerned. When I complained to the bathroom company, ("We don't wire up the timers, too many complaints!") they promised a visit within the week, but nobody showed up. Years ago I was an electrical apprentice before changing career, so I went up in the loft to have a look for myself. I was quite surprised to discover there was no fan isolator/fuse present. So I've wired one in myself with a 3A fuse using 3C+E for the permanent live.

But with regards an RCD actually being required, what are they regs these days for bathrooms?
 
But with regards an RCD actually being required, what are they regs these days for bathrooms?
All circuits for items in a bathroom require RCD protection
and so do other circuits that pass through the bathroom in zones 1&2 - although circuits in that situation are somewhat unlikely.
That has been a requirement for the last ten years.
 
The bathroom fitters / their spark needs to come back and do the job properly

Dare I ask if they gave you any certificates for the work completed?
 

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