Two electric showers.

[Gnatic]

Hi - I have an existing 9.5 kW electric shower in the bathroom. This connects to a 45amp switched fuse which is separate from the main fuse box for the house. The cable connecting shower to fuse box is pvc insulated three core (black and red pvc insulated multi-strand which is 4.0mm Od. when stripped of pvc - and a bare solid core earth). The cable outer is marked 'RISTS 300/500V BSS 6004 BASEC' and its Od. dims. are 7.5mm x 15mm.
I have just fitted a second electric shower (10.8kW) in the en suite. Can I safely take supply for this new shower via a spur from the existing shower cable - or will I be finding out what it's like trying to get Duff beer cans of the main power lines?

 

[riveralt]

Hi - I have an existing 9.5 kW electric shower in the bathroom. This connects to a 45amp switched fuse which is separate from the main fuse box for the house. The cable connecting shower to fuse box is pvc insulated three core (black and red pvc insulated multi-strand which is 4.0mm Od. when stripped of pvc - and a bare solid core earth). The cable outer is marked 'RISTS 300/500V BSS 6004 BASEC' and its Od. dims. are 7.5mm x 15mm.
I have just fitted a second electric shower (10.8kW) in the en suite. Can I safely take supply for this new shower via a spur from the existing shower cable - or will I be finding out what it's like trying to get Duff beer cans of the main power lines?

Yep and call the fire brigade.

 

[xr4x4]

another windup.

 

[holmslaw]

..

 

[automationman]

Gnatic, just trying to provide you with some good advice and I must say you are literally playing with fire here.

Both showers on at the same time will draw approximately 88 amps.
In the context of a domestic environment that is a huge amount of current from just two appliances. It is entirely possible that it could blow the main service fuse (because some are only rated at 60amps) and then you would need to call your electricity supplier and they would charge you (a huge fee) as well as report you to building control. They may even refuse to re-connect the supply. But in comparison to the house burning down, that of course, would be the lesser of the two evils!

You definitely can not connect the new shower to the existing shower and you really need to call a registered electrician who is able to self certify.

 

[automationman]

another windup.

I fear not. I suspect (unfortunately) its a genuine enquiry... shame the op did not ask before buying the second shower which presumably will be sold on ebay soon.

I have a similar question: Just bypassed my service fuse with a cast iron frying pan and joined the red wire and black wire together with the bumper from a 1967 ford escort. As I look out the window I see a small green shed on fire at the end of the street and everyones lights appear to have gone out. Will I be able to add an additional instantaneous water heater to this same circuit and still be able to use my combi boiler for mowing the lawn?

 

[ban-all-sheds]

I fear not. I suspect (unfortunately) its a genuine enquiry... shame the op did not ask before buying the second shower which presumably will be sold on ebay soon.

Shame the OP didn't stop to think whether the fact that he knew he knew nothing about it meant that he shouldn't have just gone off and done something assuming that all the things he knew he didn't know about would be OK.

As I look out the window I see a small green shed on fire at the end of the street

 

[automationman]

B-A-S, yes thats it... you are in the same street!! My sincere apologies about the loss of power. I'll go right down to the sub-station and use my other cast iron frying pan to replace the 11KV breaker. I'm certain it will be absolutely fine. Though I do need to get back in time to place a bid on that 10.8KW shower

 

[westie101]

. I'll go right down to the sub-station and use my other cast iron frying pan to replace the 11KV breaker. I'm certain it will be absolutely fine.

OI That's my job!


Though I have seen a burnt out main fuse replaced with a (stolen) claw hammer

 

[automationman]

To meet disconnection times a claw-hammer may be employed as a protective device provided:

1- it is not the property of the qualified supervisor
2- it has been stolen or borrowed from a non-competent person
3- the breaking capacity is greater than 1MKA
4- the degree of protection offered is no less than that offered by an equivalent frying pan.

BS7671: 411.3.2.2-sub-claws 1

 

[Gnatic]

Thanks guys. Reading carefully through all you've said I get the faint impression that my proposal might not be such a good idea after all.
Ebay it is.
Thanks for your advice.
Wonderful thing, electricity...

 

[automationman]

Gnatic, no offence with the jokes, just an excuse for a bit of a laugh. But seriously it may be wise to have a registered electrician call in to look at it for you. If possible at all then it would need to be on a completely different dedicated circuit but the main point is that your incomming mains may not support the large load of two showers. An electrician will be able to determine that for you and then quote you for the work. It is after all notifiable work.

Good luck.