Electric shower and RCD

[newbuildinstaller]

I want to relace a 13 year old shower, the new one MIRA jump says it needs a 30ma RCD, this is the mains board where there is a RCD is this adequate? View media item 63530 View media item 63529
Any help would be great

 

[RF Lighting]

Whilst the installation is not compliant with regs, your circuit is RCD protected, so you can replace the shower.

What rating is the new shower?

 

[PrenticeBoyofDerry]

Whilst the installation is not compliant with regs, your circuit is RCD protected, so you can replace the shower.

RFL, Why is this meter not compliant with regs?
Other than the ISO is only rated at 63A and there seems to be a much higher load on it! and pop out blanks!

 

[newbuildinstaller]

its 8.5kw mate

 

[RF Lighting]

Up front RCD is prohibited by regulation 314.1

 

[newbuildinstaller]

Up front RCD is prohibited by regulation 314.1

Is that bad? I want this doing right or not at all, its for an old lady without much money so Id rather not do the job then do it wrong

 

[RF Lighting]

its 8.5kw mate

Then you require a 40A circuit for this shower. At present you have a 32A circuit which is not sufficient.

You will need to have the circuit inspected by a competent electrician. If you are lucky, it may be possible to increase the circuit to 40A, if not, it will require rewiring with larger cable.

 

[RF Lighting]

Up front RCD is prohibited by regulation 314.1

Is that bad? I want this doing right or not at all, its for an old lady without much money so Id rather not do the job then do it wrong

It's not really unsafe, just a PITA if you get a fault as it will take out the entire installation. In an ideal world you would have the consumer unit replaced, but if money is tight, it can slip down the priority list a bit.

 

[newbuildinstaller]

cable is 10mm at present, the shower im taking out is 8.5 and has been there 13 years.

 

[PrenticeBoyofDerry]

Hmmmmm not up to current regs maybe:
But
(iv) reduce the possibility of unwanted tripping of RCDs due to excessive protective conductor (PE) currents not due to fault.

That would be the high load then, rather than one RCD covering all circuits

 

[RF Lighting]

Are you sure it's 10mm² cable? It would be very unusual for a shower of that age to be run in anything bigger than 6.0mm²

Just because something has been wrong for many years, does not mean you can turn a blind eye to it.

If you went to replace a boiler and the gas supply was undersized, would you just carry on as it's been like that for years, or would you bring the supply up to regs as part of the job?

 

[PrenticeBoyofDerry]

Is that bad? I want this doing right or not at all, its for an old lady without much money so Id rather not do the job then do it wrong

You could have the shower on an separate unit "Mini CU" external to the existing one.

 

[RF Lighting]

Hmmmmm not up to current regs maybe:
But
(iv) reduce the possibility of unwanted tripping of RCDs due to excessive protective conductor (PE) currents not due to fault.

That would be the high load then, rather than one RCD covering all circuits

You missed 314.1 (i)

Also 314.2 if you like.

 

[newbuildinstaller]

Are you sure it's 10mm² cable? It would be very unusual for a shower of that age to be run in anything bigger than 6.0mm²

Just because something has been wrong for many years, does not mean you can turn a blind eye to it.

If you went to replace a boiler and the gas supply was undersized, would you just carry on as it's been like that for years, or would you bring the supply up to regs as part of the job?

Nicely put mate. Could be 6mm cable, would 6mm cable be enough for 8.5kw?

I love simple jobs, I will be getting my sparkie mate to come over like but would like to know what he would be up against

 

[RF Lighting]

Is that bad? I want this doing right or not at all, its for an old lady without much money so Id rather not do the job then do it wrong

You could have the shower on an separate unit "Mini CU" external to the existing one.

That seems like an awful waste of money which could be put towards bringing the whole installation up to standards.