Underfloor heating mat and bathroom isolation

[scorpiouk]

Hi guys,
Having some work done in the bathroom. When finished the installer will have fitted a small heating mat under the new bathroom floor (<300W). I have a few questions about connecting it up.

Previously the bathroom had a 6mm cable running from a wylex fuse box (with MCB type fuses), to a shower. This will no longer be required in the new setup..

I was hoping I could repurpose the cable, change the MCB to a 6A type, connect it to a RCD and then feed the Heating and a small extractor fan from this..

I was planning on using one of these: here
Install on the outside, above the bathroom door.. Does this RCD give me the required level of isolation? Or do I need the isolation and the RCD.

I have been unable to find an RCD that fits the old wylex fuse box, unless anyone know diffrent.

Hope this makes sence..


thanks

 

[Taylortwocities]

I assume that your CU does not have RCD protection? If your Wylex board is of a more recent type then you could put in a 6A RCBO

This would give you the RCD protection and current protection.

The Powerbreaker RCD would do what you need with a 5amp fuse in it, without doing any changes to the consumer unit.

BUT yoiu should be aware that the work you are contemplating (electrical work in the bathroom) is notifiable, so you'll need to be telling your local authority before you do anything and be prepared for them to want to inspect the work as it progresses. They'll probably expect you to be able to test and certify it all on completion.

Or you could get a registered electrician to do it for you! A much cheaper option for a simple job like this.

 

[scorpiouk]

Thanks for the reply...

Your correct there is no RCD in the CU..

Good point about the 5amp fuse..
The change to the CU is just belt and braces, prevents someone adding more load later.

I know it notifiable, but lots must be installed without being checked.

 

[deadshort]

What TTC said

Post a pic of the CU please, we can see if you can fit a RCBO.

DS

 

[scorpiouk]

Thanks for the reply..

this is the same unit, but not my picture here

 

[deadshort]

No sorry, these are too old for retrofit rcbo's.

Your solution is fine remember the 5a fuse ! You don't have to derate the 32a mcb as the cable is 6mm.

Regards,

DS