Electric Shower from a sub board

[vwes59]

Hi. I'm being tasked with installing an electric shower into a property that was built back in the 1980's. The main consumer unit has only 4 ways and is protected by an RCD, and is fully populated and in a very tight space under their stairs. However one of the MCB's is currently used to feed another board in their attached garage, which does have spare ways.

So my thought is, rather than mucking about with the existing main board and trying to squeeze in a new board, which I doubt will fit, is there anything stopping me from using the sub board ? I know I'll have to upgrade the MCB and cable to the garage to do this (It's currently a 32A MCB, 6mm cable), but that's not a pain, as luckily the main board is not far from where the sub board is located, and I've got a feeling the bathroom where the shower is going to be fitted is directly above the garage. The client hasn't bought the shower yet, so I do have some control over what they buy with regards to wattage.

If anyone knows why that wouldn't be a good idea please let me know - I certainly can't see a reg that this breaches.

 

[Taylortwocities]

Hi @vwes59
I guess, from your question, that your core skill is more plumbing than electrical? If that's the case, I really suggest that you get a competent electrician to do this. Its not as easy as upping the MCB and banging in a bigger cable.

In any case, what you plan is going to create a new circuit, and thats notifiable work. So compoetent and registered electrician needed. Sorry.

 

[Risteard]

Hi. I'm being tasked with installing an electric shower into a property that was built back in the 1980's. The main consumer unit has only 4 ways and is protected by an RCD, and is fully populated and in a very tight space under their stairs. However one of the MCB's is currently used to feed another board in their attached garage, which does have spare ways.

So my thought is, rather than mucking about with the existing main board and trying to squeeze in a new board, which I doubt will fit, is there anything stopping me from using the sub board ? I know I'll have to upgrade the MCB and cable to the garage to do this (It's currently a 32A MCB, 6mm cable), but that's not a pain, as luckily the main board is not far from where the sub board is located, and I've got a feeling the bathroom where the shower is going to be fitted is directly above the garage. The client hasn't bought the shower yet, so I do have some control over what they buy with regards to wattage.

If anyone knows why that wouldn't be a good idea please let me know - I certainly can't see a reg that this breaches.

It's far from an ideal solution, for one being any Earth fault will cause the entire installation to lose power. My more immediate concern would be the current rating of the existing RCCB though before adding substantial loads to it.