Old circuit - can I replace MCBs with RCDs?

[OtleySpark]

Our house has a TN-S system and the consumer unit has only a main switch and mcbs. There are no RCDs on any circuits apart from a single socket in the conservatory.

Reading up (for a coming exam) I see in the On-Site Guide 3.6.1 that RCDs are required for (amongst other locations):
ii. socket outlets where used by ordinary persons for general use
iii. for all circuits of locations containing a bath or shower.

Does this mean the circuit would fail an inspection?

Can I replace the existing MCBs with RCDs (they are Hagar type 2 M6) or is it a case of having to replace the consumer unit too?

Thanks

 

[telectrix]

best way forward is change the CU for a dual RCD CU. bear in mind that you would need to trace any leakage faults/shared neutrals, upgrade earthing and bonding if rquired. full set of circuit tests........

 

[Sparkyphill]

Our house has a TN-S system and the consumer unit has only a main switch and mcbs. There are no RCDs on any circuits apart from a single socket in the conservatory.

Reading up (for a coming exam) I see in the On-Site Guide 3.6.1 that RCDs are required for (amongst other locations):
ii. socket outlets where used by ordinary persons for general use
iii. for all circuits of locations containing a bath or shower.

Does this mean the circuit would fail an inspection?

Can I replace the existing MCBs with RCDs (they are Hagar type 2 M6) or is it a case of having to replace the consumer unit too?

Thanks

Yes it would fail, it all boils down to cost a new board is about 60 quid so price up the replacement parts and decide from there

 

[Sparks71]

Yes the installation would fail a test and inspection due to the lack of RCD protection.
Hager have changed the style of he MCB,S so an rcbo will not fit.
Suggest the easiest way forward is to buy a 17th edition board with 2 rcd,s and associated protective devices.

dont forget this work will fall under part p and will need to notified to building control.

 

[telectrix]

why would it fail an inspection? if the installation is in good order and complied with a previous version of the wiring regs. then a few C3's would be appropriate.

 

[markc123]

It would get at least a c3 on a condition report, depends on the actual condition of the old board IMO, if theres wholes in that you can fit your fist through then it'll fail.

Not one electrician can make a customer change the board, its just advised too have a 17thed board these days - when your current setup was installed it woulda been perfectly fine...you're the customer / practicing electrician in this case, so if i were you, i'd want the board changing.

 

[telectrix]

make sure your insurances are up to date. public liability if you are going to change the board. life cover if you are not,
.

 

[MDJ]

Our house has a TN-S system and the consumer unit has only a main switch and mcbs. There are no RCDs on any circuits apart from a single socket in the conservatory.

Reading up (for a coming exam) I see in the On-Site Guide 3.6.1 that RCDs are required for (amongst other locations):
ii. socket outlets where used by ordinary persons for general use
iii. for all circuits of locations containing a bath or shower.

Does this mean the circuit would fail an inspection?

Can I replace the existing MCBs with RCDs (they are Hagar type 2 M6) or is it a case of having to replace the consumer unit too?

Thanks

Is the ZE reading over or under 0.80 ohms, and was the Job up to standard when the existing Board was installed?

 

[Octopus]

Having read some of your earlier posts, maybe you should do a bit more training before embarking on up grades in your own house.

Do you own a MFT?

 

[OtleySpark]

Having read some of your earlier posts, maybe you should do a bit more training before embarking on up grades in your own house.

Do you own a MFT?

Yes, i'm still learning. I did a complete rewire of an old house back in 1990 - but things were less bureacratic then! It did pass inspection too at the time.
I was just doing some revision for an upcoming test and it asked me to check my home installation. It was then I saw that the CU only has MCBs.
I do have A MFT (if you mean multi-function tester).

 

[markc123]

You shoulda probably put in your OP then that you wern't actually planning on changing it, just enquiring for an exam buddy - it did sound like you were planning to do the work yourself.

Good luck with the learning and good luck with the up and coming exam. all the best.

 

[telectrix]

issue boils down to competence. if you are competent to change the CU and any related issues such as earthing and bonding, testing and certification, then go ahead and do it. you may then want to do as around 10% do, and notify it to your LABC. be prepared to find your bank balance depleted by a further £300 though.

 

[Sparkyphill]

why would it fail an inspection? if the installation is in good order and complied with a previous version of the wiring regs. then a few C3's would be appropriate.

Your right but I prefer to see RCD's especially if it's my name on the cert

 

[OtleySpark]

issue boils down to competence. if you are competent to change the CU and any related issues such as earthing and bonding, testing and certification, then go ahead and do it. you may then want to do as around 10% do, and notify it to your LABC. be prepared to find your bank balance depleted by a further £300 though.

Thanks very much for all your replies.

I'll stick to my revision for now and put it all on my to do list...

 

[Octopus]

Thanks very much for all your replies.

I'll stick to my revision for now and put it all on my to do list...

I'm guessing you'll need Part P membership when you want to get up and running so I'd do a CU change for your assessment with Elecsa and you'll have that covered too.