Extending Shower Supply

[PaulC59]

I need to replace my instant electric shower. However, the new shower I have bought has the cable entry points on the Opposite side to the old unit and I need to extend the supply by approximately 300mm. Can anybody advise me on if this is acceptable under part P and if jointing is ok what if any restrictions apply to such a cable join.

Many thanks

 

[sm1thson]

sorry to not answer your question, Ill leave that to someone who knows better, but in the meantime to help them: (because if i dont ask someone elsewill) what rating is your new shower? what size cable do you have?(the existing cable in the wall) what size fuse is it? is it protected by an RCD?

 

[BigJon]

All joints should be accessible for inspection/repair. Is it possible to re-wire from switch to your new shower, its not good practice to joint cables inbehind walls where they arent accessible incase they fail.

 

[PaulC59]

Many thanks for your replies.

My fault I should have made my explanation more clear. The shower is 8.5KW and is cabled in 6mm with a 40amp MCB. The existing cable is routed in trunking with a cable run of about 8m.

The existing cable is long enough to enter the shower housing but is 250/300mm to short to connect to the terminals. The joint(s) will be within the shower housing using the terminal block from the old 9.6KW triton shower. I had considered re-cabling, but that would require retiling and as I understand it, the work would be notifiable under part “P”.

I was simply hoping that the join would be acceptable.

 

[Adam_151]

I'd use the crimp connectors you can get that are oversleeved with adhesive lined heatshrink.

I'd be loathe to use terminal blocks or other types of crimps, because I beleive some of these shower units do allow a small amount of water to 'leak' into the casing, the manufactorers terminals would have been positioned in such a place where this won't cause any problems

 

[kevnurse]

You didn't mention if you have a double pole isolation switch between the mcb and the shower unit. I would be tempted to run a replacement cable between the switch and the new shower rather add a junction. If you don't have a DP switch, this is an ideal opportunity to fit one.

 

[PaulC59]

Thanks for all the help.
The circuit does have a double pole isolator switch, in fact the whole installation is only a couple of years old. The Triton shower "boiler" and PRD have both failed an the spare parts were considerably more than a replacement shower.