Replacing CU off peak supply

S

Steven1875

Joined
22 Aug 2022
Messages
3
Reaction score
0
Country
United Kingdom
Hi

I’m due to move into a 3 bedroom flat in a few weeks. Im thinking of replacing a CU that has off-peak supply with 3 mcb’s, no RCD, for 3 storage heaters. There is a separate CU for everything else in the flat. I want to add two more storage heaters (Dimplex Quantum), and there is space on existing CU but I’m told from 2024 it’ll need to be Rcd protected. So, was thinking of replacing the CU at the same time.

My question is: should I buy pre-loaded CU, and change mcb’s to all 16a( is that correct size? I don’t have access to flat to check what’s already there), or empty CU and fill with the 5 correct size mcb's?

Storage heater sizes (approx): 4x2.5kw, 1x1.7kw.

Any advice appreciated.
 
What will be required in 2024 is not relavent as the regs are not retrospective.

Changing a CU is notifiable work and that comes with a hefty fee. Usually cheaper to get a sparks to do it.
 
Steven1875 said:
but I’m told from 2024 it’ll need to be Rcd protected.
Click to expand...
Told by who?
There may well be a new version of BS7671 by then, but it hasn't been written yet, and any details of what it will eventually contain is not available.

Most circuits in dwellings already need RCD protection regardless of what they are supplying.

Consumer units are purchased as what you want. Absolutely no sense in buying one set of things and then changing parts to something else.
 
Under the current (18th) edition of BS7671 fixed equipment such as storage heaters does not generally require RCD protection per-se. However cables concealed in a wall normally require RCD protection. There are exceptions to the RCD protection rule for concealed cables but making use of those exceptions is likely to substantially increase the cost of instaling the cabling.

There is not in general any obligation to update your installation to the latest edition of BS7671. However most electricans will insist that any new work done complies with the latest edition. If the consumer unit is from a range where parts are still available then RCBOs are an option for providing RCD protection without replacing the whole CU. It may also be possible to replacing the incoming device in the CU with a RCD, I would not recommend a single RCD configuration for a main CU, but for a dedicated off-peak board it would seem more acceptable.

Private rental properties in england are required to get a satisfactory EICR, but even there current industry guidance seems to be that meeting 16th edition standards on RCD protection is sufficient to get a satisfactory EICR.

Under english building regulations, replacing a CU or creating a new circuit are notifiable works. In practice notifiable works means that doing the work legally either using an electrician who is registered to self-certify or considerable hassle and expense dealing with building control.

I have no idea what the situation is in scotland.
 
Steven1875 said:
I checked with my brother (who owns a couple of rental flats) who had mentioned the Rcd regs in 2024 and it turns out it only applying landlords:
Click to expand...
What you have linked to relates specifically (and only) to Scotland (Scottish legislation) - is that where you are?

As you have been told, in the absence of crystal balls, we have no idea what may be happening to the Wiring Regulations (BS7671) and/or any legislation (related to rented property or anything else) in England and Wales in 2024.

Kind Regards, John
 
Yes, I’m in Scotland (Glasgow).

I note the use of a qualified electrician and their ability to self certify.

Thanks.
 
You must log in or register to reply here.
Back
Top