9.5kw shower installation

[dino89]

hi
purchased this shower to replace an old one but didnt check cable size prior
the old shower is installed with 6mm wire will this be ok for the new 9.5kw shower
thanx

 

[fattony]

I would say you have two options here, rewire the shower in a 10mm cable or take the shower back to the shop and exchange it

 

[Steve]

not nessecarily

6mm is rated max 47 amps. a 9.5kw shower draws about 40.

However, it all depends on the route of the cable and how long it is.

 

[GaryMo]

Agree with Steve, more information is needed.

 

[dino89]

the run is from CU/ RCD up wall , under floor boards across landing and then up into airing cupboard striaght through wall to shower approx 5-7 metres of cable whats max acceptable cable run and does this sound OK or not
thanx

 

[fattony]

yes it can carry approx 47A and the 9.5kw shower draws 41A, but it depends on the installation method and length of run, 5-7m does that include the cable which runs to the 45A switch (you dont mention it)

 

[dino89]

with the 45 amp its probably about 10 metres of 6mm cable

 

[GaryMo]

You mention RCD, where exactly is the shower fed from?

eg MCB from RCD protected side of a split load consumer unit?
RCBO from a non RCD protected consumer unit?
Rewirable fuse to an RCD then out to shower?

 

[dino89]

it comes from a old style wired fuse box

 

[GaryMo]

it comes from a old style wired fuse box

So fusewire?

If so then forget running a 9.5KW shower on a 6mm cable.

 

[dino89]

yep fuse wire getting new trip box soonish but could of done with a shower so is it best to exchange it for a lower rated shower? say 8.5 kw or what size? or run 10mm wire on this box
thanx

 

[fattony]

All shower manufacturers recommend shower circuits are protected with an RCD, although I believe this is a recommendation not a requirement everyone on this site (I hope) would always insist on a shower being protected with an RCD.

Get the consumer unit replaced or at least have a separate RCD installed adjacent to the consumer unit before having the shower installed. Your safety is worth much more then saving a few quid.