Change a heater into a socket

[Taylortwocities]

am allowed to change that MCB into an RCBO myself,

You are permitted top do this, but how would you test that the RCBO is working to spec. Do you have an RCD tester?

as long as I can use a screwdriver without stabbing myself?

Stabbing with a driver may not be as serious as electrocution. Only you can judge your competence to isolate the CU so that you can safely perform an organ transplant on it.

 

[sparkwright]

In the case of an electrical installation - a re-wire, a new consumer unit, a partial rewire, an attempt to get some or all of the installation to current regs etc etc etc.

 

[ban-all-sheds]

So would adding a spur count as a partial rewire?

 

[Wet_One]

You are permitted top do this, but how would you test that the RCBO is working to spec. Do you have an RCD tester?

Fair to say that if I had a £400 tester, I wouldn't be asking such basic questions. So I will have to rely on the little button

Stabbing with a driver may not be as serious as electrocution. Only you can judge your competence to isolate the CU so that you can safely perform an organ transplant on it.

Facetiousness aside, yes I am competent to safely isolate the CU (and then confirm it is actually isolated) and swap out a MCB.

The current MCB is a Hager MT116 16A 1 Pole Type B Miniature Circuit Breaker
https://uk.rs-online.com/web/p/residential-mcbs/2623633/

So I guess it makes sense to swap it for a Hager Reduced Height RCBO Type B Single Pole 16A 6kA 30mA ADA316G
https://www.eleconline.co.uk/hager-...-rcbo-type-b-single-pole-16a-6ka-30ma-ada316g

Or will a British General 16A 30mA SP Type B Mini-RCBO clip in just as easily? (Since the previous isn't available from Screwfix)
https://www.screwfix.com/p/british-general-16a-30ma-sp-type-b-mini-rcbo/7067x

 

[Taylortwocities]

You must not mix manufacturers. Would you fit a Kia oil filter in your Porsche?
A consumer unit is type tested by Hager and certified as working correctly with their own products.
Buy the Hager RCBO.

But it still needds testing. The "TEST" button is a basic test of the mechanics of the device, it does not test that the RCBO conforms to the current and trip time characteristics.

 

[Wet_One]

I can fit the same Unipart oil filter in a Toyota, a Daihatsu, a Daewoo or a Suzuki
But I do take your point, thank you.

On a related note, I do plan to have a major bathroom refit with a power shower so I'll be getting a sparky in at that time. Maybe I should consider a new CU with RCDs for everything inside it?

 

[Taylortwocities]

Always a good plan. But you still need to fit the RCBO for now,

 

[ban-all-sheds]

Or an RCD socket.

 

[sparkwright]

So would adding a spur count as a partial rewire?

Fair point well made.

 

[Wet_One]

Okay, I have hit a snag:

Here is the CU with the MCBO in place:

The MCB had a single terminal at the top with two red wires in it.

The RCBO has two terminals 'Load L Out' and 'Load N Out'
I placed both red wires into the Load L out terminal and left the other empty.

When I switch on the MCBO with nothing plugged into the socket, it stays latched. But turn anything on and it trips.

What have I cocked up?


EDIT: am I supposed to take the black N that goes to the circuit and remove it from the N bar at the top of the CU and move it into the RCBO?

 

[EFLImpudence]

am I supposed to take the black N that goes to the circuit and remove it from the N bar at the top of the CU and move it into the RCBO?

Yes, but both of them.

 

[Wet_One]

So the two Red wires from the circuit both go the 'Load L Out' and the two black wires from the circuit go to the 'Load N Out' on the MCBO and the blue wire from the RCBO goes to the N busbar ?

 

[EFLImpudence]

Yes.

 

[Wet_One]

I have a strong desire to give you a big hug.

Thanks also to the others who gave help. It's a great feeling to know that not only did I do something that worked, but it is legal and, more importantly, completely The Right Way to do it.

 

[Taylortwocities]

It's a great feeling to know that not only did I do something that worked, but it is legal and, more importantly, completely The Right Way to do it.

But it’s not been tested.