Replacing an electric shower 8.5Kw with a 10.5Kw

[chris_DIY]

Hi all,

This is my first post & it looks like its a fairly familiar topic, but I'm gonna ask it anyway....

We are re-doing our bathroom and want to replace a 8.5 Kw electric shower with a 10.5 one, do I need to get the power cable from the consumer unit upgraded?

The new unit says 10.5Kw @ 240V 9.6KW @ 230V 45A MCB rating ~ but I dont understand what MCB mean; I can check what the fuse is in the CU, but not till tomorrow now.

Sorry, I’m not sure of the “core size” of the existing cable, but the width of the entire grey casing is about ½” wide. would that make it 6mm2?

Should I get this changed, will the other cable get hot & be a risk if I don’t do it, now is the time to do it because the bath room is gutted ready for re-tiling.

Its a pretty long run from the unit to the shower, at a guess 25-30 feet.

Many thanks for you help.

Chris

 

[andy]

new cables needs to be 10mm^2. and do you have RCD protection?

youll need a 45A MCB or 45A fuse

 

[Big_Spark]

Chris, as it sounds as if you still have BS3036 fuses, or possibly Ceramic equivelents, it may be a wise idea to call in an Electrician to see if your existing board can take the upgrade from 8.5kW to 10.5kW. The jump may not be much, but it could be a problem. Some of the older boards do not support fuses in excess of 40A.

The cable should be 10mm^2 as suggested by Andrew, so this is likely to need an upgrade.

 

[chris_DIY]

thanks for the replies.

I will be getting a electrician to do the work, this is not something I would contempate (sockets & lights are Ok, this I am not sure about).

Yes, I have got an old fuse box, the shower cable going into it is fused with a 45A "mini-cut out?", (the other cables going in use the old ceramic fuses)

BUT have also got a new RCD unit as well, put in when our house extension was done (dont ask why it wasnt changed at the time...!..££££, or lack of) - there are spare slots in this unit, so presumably a new wire could be run from that one to replace the existing cable?

Also How much would you expect to pay to get the old ceramic unit changed to the more modern type?


Chris

 

[andy]

Also How much would you expect to pay to get the old ceramic unit changed to the more modern type?


Chris

await coments and link.... (which i cannot be bothered to find, but its #9 on the list)

 

[supersparks]

this forum won't let anyone give figures or prices on any work...not sure why...

try www.ask the trades.co.uk (without spaces)
or www.screwfix.com to ask about prices.
there are plenty about, search for electrical questions or the like

hope your quick! this post will be removed pretty fast as its linking to forums which allow you to ask for prices, sadly the gestapo on here dont like it.

anyway, it depends on your area?

 

[chris_DIY]

many thanks to all who replied.