UK Inspection Report, Electric Shower, Merlin Gerin and Schneider MCBs

[Iain Stewart]

Hello,
We live in an old stone built ground floor flat, built in the 1880s. Obviously the consumer unit and cabling has been updated a number of times over the years by previous owners. One being the Local Authority who owned the property back in the 1960s -70s.

We have lived here for 25 years and decided to have an electrical inspection carried out by a local Electrician. He is a good honest guy, fully trained and qualified and a member of quite a few registered bodies. His report has shown only a couple of problem areas that should be addressed. Separate circuits for appliances, swapping circuits to the protected side of the consumer unit, updating sockets and light switches. He says although our consumer unit is older and the cabling is older there is no need change it or renew at this time but it is something we should think about for the future. He did have limited knowledge with regard to our particular make/model of consumer unit. (Young guy probably not born when our consumer unit was installed)

Now, our plan is to sell up in the new year and realising that this would be a huge upheaval and at a hefty cost we have decided to not take on the task.
However, we have hit a juncture. Our plumbing is such that we have only ever had an Electric Shower.
We wish to maintain this arrangement but have decided to upgrade the shower to a more powerful 10.5Kw unit as the old 7.5Kw shower has packed in and as you have no doubt guessed, this will involve a cable and MCB upgrade.

Existing arrangement is; distance from consumer unit to shower, 25m. Cabling 6mm², under floor in solemn space and in plaster for the last 1m. 32amp MCB on RCD protected circuit.
Our fuse box is an Merlin Gerin, (photos attached).

My questions are; (bearing in mind we are not changing the consumer unit and only wish to change the cabling and MCB for this one circuit),
Q1, would the Merlin Gerin consumer unit be able to be upgraded with a modern Schneider Acti9 45 amp MCB in place of the Multi9 MCB.
Q2, Are our current Multi9 MCBs a C-curve? I'm not sure if the writing on the current MCBs indicate the Curve type.
Q3, Would the Schneider replacement MCBs need to be a C-Curve or B-Curve type in whichever case?
Q4, Rather than a consumer unit upgrade, could we actually just update all the MCBs in the consumer unit this way?
Q4, Should we upgrade all the MCBs to RCBOs instead. (Assuming there is room in the consumer unit for such an upgrade as I understand they are quite large in comparison).

From my internet of things investigation... I gather that Merlin Gerin are no longer in manufacture and subsequently that the proper replacement for Multi9 would be Schneider Acti9. Would this be the correct information?

Any good advice appreciated for 3 dirty children and a smelly wife... I've always been a clean guy...

 

[davesparks]

Hello,
He is a good honest guy, fully trained and qualified and a member of quite a few registered bodies.
He says although our consumer unit is older and the cabling is older there is no need change it or renew at this time but it is something we should think about for the future. He did have limited knowledge with regard to our particular make/model of consumer unit. (Young guy probably not born when our consumer unit was installed)

Existing arrangement is; distance from consumer unit to shower, 25m. Cabling 6mm², under floor in solemn space and in plaster for the last 1m. 32amp MCB on RCD protected circuit.
Our fuse box is an Merlin Gerin, (photos attached).

My questions are; (bearing in mind we are not changing the consumer unit and only wish to change the cabling and MCB for this one circuit),
Q1, would the Merlin Gerin consumer unit be able to be upgraded with a modern Schneider Acti9 45 amp MCB in place of the Multi9 MCB.
Q2, Are our current Multi9 MCBs a C-curve? I'm not sure if the writing on the current MCBs indicate the Curve type.
Q3, Would the Schneider replacement MCBs need to be a C-Curve or B-Curve type in whichever case?
Q4, Rather than a consumer unit upgrade, could we actually just update all the MCBs in the consumer unit this way?
Q4, Should we upgrade all the MCBs to RCBOs instead. (Assuming there is room in the consumer unit for such an upgrade as I understand they are quite large in comparison).

From my internet of things investigation... I gather that Merlin Gerin are no longer in manufacture and subsequently that the proper replacement for Multi9 would be Schneider Acti9. Would this be the correct information?

I would say there is no point replacing that consumer unit, short term or long term, it is a good quality board designed primarily for commercial/industrial use rather than domestic and any modern domestic CU would be a step backwards in my opinion.
The electrician not being familiar with that CU is may be due to them primarily working in the domestic sector rather than commercial or industrial.

Schneider have bought Merlin Gerin but are still manufacturing compatible protective devices. To bring it up to full compliance with current regulations you would need to change the non-RCD ways to RCBO's.
Whilst you can buy new compatible protective devices there is still a massive amount of the older type out there, mostly second hand or some new old stock.

The MCB's you have use an older labelling system than the current B, C, D, the but that says type 2 denotes the tripping curve.

 

[freddo]

Those are nice consumer units. I like the 'upside down' configuration of the busbar.

 

[Iain Stewart]

I would say there is no point replacing that consumer unit, short term or long term, it is a good quality board designed primarily for commercial/industrial use rather than domestic and any modern domestic CU would be a step backwards in my opinion.
The electrician not being familiar with that CU is may be due to them primarily working in the domestic sector rather than commercial or industrial.

Schneider have bought Merlin Gerin but are still manufacturing compatible protective devices. To bring it up to full compliance with current regulations you would need to change the non-RCD ways to RCBO's.
Whilst you can buy new compatible protective devices there is still a massive amount of the older type out there, mostly second hand or some new old stock.

The MCB's you have use an older labelling system than the current B, C, D, the but that says type 2 denotes the tripping curve.

Thank you for your reply davesparks.

That sounds very good advice to me and I am delighted to hear that the CU is of good quality.
I think I will try to source the original MCBs from the internet and ask my Electrician to do the job for me. He quoted me a very reasonable £250 labour for the original work of running another cable to my kitchen, (both the oven and hob are on the same cable and have a dual outlet plate in the kitchen), he recommends that needs to be changed. Also to swap the cooker circuit to a lower amperage MCB and move it to the RCD protected ways... I guess I would try to source three original MCBs for him to fit. He would no doubt supply everything else, cables, sockets and light switches etc... Should I source a 45amp MCB for the shower and, am I right in thinking that I should get 2 x 30 amp MCBs for both separate oven and hob circuits?

Thank you...

 

[davesparks]

He quoted me a very reasonable £250 labour for the original work of running another cable to my kitchen, (both the oven and hob are on the same cable and have a dual outlet plate in the kitchen), he recommends that needs to be changed.

Reasonable? I'd say its very unreasonable to take what sounds like a perfectly compliant and safe installation and carry out unnecessary work.

 

[Iain Stewart]

Thanks to all for your replies. Collectively I have had some great advice and gained some good knowledge with regards to my CU and the best course of action to take...
Thanks again and I wish you all a Merry Christmas and all the best for the New Year!
[automerge]1577226951[/automerge]

Reasonable? I'd say its very unreasonable to take what sounds like a perfectly compliant and safe installation and carry out unnecessary work.

No, I will ask him to do only the remedial work. I'm sure he would be asking a lot more for a 4 bedroom, 1 sitting room, 1 bathroom, 1 cloakroom and a kitchen rewire with a new consumer unit. He said half a days labour of £250 for the remedial work and in my experience over the years with various Electricians in Edinburgh, that is a good price.
It will no doubt be extra for the shower that I don't mind paying. It will probably come in around £1000 that would be fine for me...

 

[davesparks]

No, I will ask him to do only the remedial work.

That's my point, having the hob and oven on the same circuit is fully compliant with the current regulations. Suggesting that there is any need for them to be on seperate circuits is incorrect and they are ripping you off.
They may not be deliberately ripping you off, it could be through a genuine lack of knowledge of the regulations, but either way it is wrong.

There are far too many electricians who have not properly read and understood the changes in the regulations and are still working to previous editions of the regulations. This is often unintentional and they are just falling back on what they were taught as an apprentice.

 

[Iain Stewart]

I briefly spotted an accusation there in a post with regard to doing the job myself!
I wish I could that would save me a fortune... I will ask my Electrician if he will source the original MCBs but I thought I would try to make the whole thing easier... I am a researcher and the IT/internet thing is a breeze for me... I'm not so sure about the person with the doubts/accusations but hey ho! Were all entitled to our opinions right or wrong I suppose...

My wife is a registered childminder with the Care Commission. This is the reason we needed the;

DOMESTIC ELECTRICAL INSTALLATION CONDITION REPORT
Issued in accordance with British Standard BS 7671 - Requirements for Electrical Installations,
...in the first place. Safety first!

Maybe the person with the comments is just a DIYer and that's what they would do.
Also it's our house and our CU and our MCBs so I am entitled to find out as much information about them as possible. Just in case I come across the type of rip-off person who would make such comments as self installation and probably do the job themselves...

Thanks again...
[automerge]1577228091[/automerge]

That's my point, having the hob and oven on the same circuit is fully compliant with the current regulations. Suggesting that there is any need for them to be on seperate circuits is incorrect and they are ripping you off.
They may not be deliberately ripping you off, it could be through a genuine lack of knowledge of the regulations, but either way it is wrong.

There are far too many electricians who have not properly read and understood the changes in the regulations and are still working to previous editions of the regulations. This is often unintentional and they are just falling back on what they were taught as an apprentice.

Interesting, I will get clarification on this from my local authority building services dept...
The guy seems genuine to me and we like him a lot... But you never know! He is young and perhaps has not fully understood the regulations as you say.
Thanks for the great advice...

 

[davesparks]

Interesting, I will get clarification on this from my local authority building services dept...
The guy seems genuine to me and we like him a lot... But you never know! He is young and perhaps has not fully understood the regulations as you say.
Thanks for the great advice...

Local authoritys generally don't have a clue about the wiring regulations as it is nothing to do with them.

Unfortunately you have to trust the electrician you hire, or spend a few years learning the trade yourself.

Ask the electrucian to show you the actual regulation which they believe this does not comply with. The book they will show you is BS7671 'The 18th edition IET wiring regulations' (or words to that effect, I can't remember the exact wording but the BS number is right) which is an A4 size book with a blue cover (any other colour is a previous version which is not current).
They may also show you the on site guide which is an A5 size ring bound book with a blue and white cover. This is an official guide to regulations.

 

[Iain Stewart]

Local authoritys generally don't have a clue about the wiring regulations as it is nothing to do with them.

Unfortunately you have to trust the electrician you hire, or spend a few years learning the trade yourself.

Ask the electrucian to show you the actual regulation which they believe this does not comply with. The book they will show you is BS7671 'The 18th edition IET wiring regulations' (or words to that effect, I can't remember the exact wording but the BS number is right) which is an A4 size book with a blue cover (any other colour is a previous version which is not current).
They may also show you the on site guide which is an A5 size ring bound book with a blue and white cover. This is an official guide to regulations.

Here is a snapshot of section 7 of the report I may have got my information wrong... What are your thoughts please?

 

[Strima]

Those are all C3s and are only recommendations, you should have received a satisfactory report and no remedial works are required.

 

[Iain Stewart]

Those are all C3s and are only recommendations, you should have received a satisfactory report and no remedial works are required.

Yes understood , but I would like the house to be 100% goodly as far as Electrical is concerned. I am unsure as to the real-time effect of the recommendations...
What would you recommend?

 

[freddo]

I wouldn't be too worried about any of the defects listed there. Carrying out the work suggested should improve the installation, but nothing is required to be done. The certificate should state the installation is in a satisfactory condition.

 

[Midwest]

If you are moving out very soon then why bother with the hassle? Stick with a lower power shower unit.

Thats the best bit of advice you've been given (including the #4 @Wilko, which won't multi post here?). Unless anything is dangerous, and that appears not to be, I wouldn't be doing anything if you are moving soon. Ask an estate agent. I recently moved, and felt inclined to renovate certain things before putting my place on the market, but was advised not to.

The eventual buyer, never mentioned anything. If there are things that need changing or upgrading, that will be reflected in the offer price; people want to put their own mark on the property they are investing in. Which, incidentally IMO, would be replacing that horrible looking CU.

Merry Xmas everyone.

 

[Iain Stewart]

Thats the best bit of advice you've been given (including the #4 @Wilko, which won't multi post here?). Unless anything is dangerous, and that appears not to be, I wouldn't be doing anything if you are moving soon. Ask an estate agent. I recently moved, and felt inclined to renovate certain things before putting my place on the market, but was advised not to.

The eventual buyer, never mentioned anything. If there are things that need changing or upgrading, that will be reflected in the offer price; people want to put their own mark on the property they are investing in. Which, incidentally IMO, would be replacing that horrible looking CU.

Merry Xmas everyone.

Hi Midwest, got that... The report did come back as satisfactory.

However, I don't like the idea of passing on possible issues to the next person, call it good karma or something. Call me old fashioned, but my grandparents, who lived through two world wars would never have done that either.

I understand a buyer may rip it all out and that's fair enough. If we were not selling we would commission a full rewire/complete upgrade ourselves and I would insist that the highest quality CU and cabling/fittings etc were used.

As a matter of interest, what would you be replacing the horrible CU with?

Merry Christmas to you and all...

Thanks

 

[hasel5]

I would leave well alone also and you are not handing over a poor job TBH and Merlin boards are really good.

You will be hard pushed to find a board of better quality