electric shower safety/legality?

[paulmcmanus247]

I have just bought a Triton 9.5kW electric shower, not yet installed, but have been told the electric wire (thickness 6mm?) may not be enough for the shower and as such is illegal & unsafe? Is there any truth in this? Thanks...

 

[RF Lighting]

Quite possibly.

 

[baz1968]

The size of cable needed depends on the loading, (9.5 KW), the cable route (will it run through insulation etc.) and the length of run from the CU.

The installation is notifiable to Part P

See here for more info. http://www.diydoctor.org.uk/projects/electricshower.htm

 

[ban-all-sheds]

You should avoid that site like the plague - they lie to people about what the Building Regulations actually say because they think they know best what people can be trusted to know.

I have just bought a Triton 9.5kW electric shower, not yet installed, but have been told the electric wire (thickness 6mm?) may not be enough for the shower and as such is illegal & unsafe? Is there any truth in this? Thanks...

6mm² twin & earth (and you don't seem 100% sure that that's what you have) can safely carry 47A. Or a maximum of about 10A.

It depends on how the cable is installed, where it runs, what type of fuse/MCB you have - there are several different factors to consider.

OK - the 10A figure is very unlikely to be what your cable can carry, but your shower needs about 40A, and the only safe answer that anybody can give without more information is that your existing cable is not suitable, it is unsafe and therefore it would be illegal to use it.

 

[Anteaus]

There are as many different opinions on cable ratings as there are cables. And then some.

Basically, 6mm should be adequate provided the cable is protected by a 40A breaker (MCB) and NOT run under or inside thermal insulation, and provided it's not trunked-in along with other high-current cables.

It might also be necessary to use a heavier cable if it's a very long run, owing to voltage-drop considerations. Unlikely in a domestic house, though.

A point I would add is that a shower is one of the more safety-critical electrical jobs, and if you are at all unsure I would call in a professional. At the very least make sure the shower pipework and any adjacent metal, e.g taps, are properly cross-bonded, and preferably fit an RCD to the circuit.

Dont forget that 40A cable connections need to be T-I-G-H-T, too, or you may have a fire on your hands at some later date.

 

[ban-all-sheds]

At the very least make sure the shower pipework and any adjacent metal are properly cross-bonded.

Unless the plumbing is, or is predominantly, plastic...

 

[DESL]

I have just bought a Triton 9.5kW electric shower, not yet installed, but have been told the electric wire (thickness 6mm?) may not be enough for the shower and as such is illegal & unsafe? Is there any truth in this? Thanks...

Who told you? I assume this (hopefully) was an electrician.

I think it would be a good idea to contact a professional electrician.

http://www.competentperson.co.uk

There are loads of electricians in Armagh on the approved list.

 

[ColJack]

I take it you meant 10KW BAS, not 10A????

 

[securespark]

It is not recommended that you use plastic capping for this type of supply.

Why?

If you use wall mounted switches, the rocker type, then these should not be mounted inside the room containing the shower but on an exterior wall to the room, unless it is possible to mount the switch at least 2.5 meters from the shower.

Where is that figure mentioned?

It would be a wise precaution to check all the pipework for cross-bonding when you install the shower. All copper pipes should be cross-linked using EC14 Earth clamps, as described above, and lengths of 4mm2 green/yellow earth cable using crimp lugs on the ends. There should be a main Earth bond linking your consumer unit earth terminal or the main earth terminal of the supply to both your Gas and water supplies, these bonds should be within 600mm of the consumer side of meter or stopcock.

No mention of supp bonding to cpc's...

All the advice contained here is in accordance with BS7671: 2002

Really?

HEIGHT OF ELECTRICAL SOCKET AND SWITCH OUTLETS
The building regulations ( Not Scotland) state that switches and sockets in houses should be installed in a way that persons with limited reach can use them easily.

The suggested heights are, for socket outlets, no lower than 450mm from the floor and for switches, TV points, telephone outlets, doorbells etc, no higher than 1200mm from the floor.

Unless the house is specifically designed for a person with limited reach these requirements do not apply in garages and kitchens.

 

[ban-all-sheds]

I take it you meant 10KW BAS, not 10A????

Nope.

Several cables bunched together, buried in insulation, ambient temperature 40°, protected by a rewirable fuse...

Actually - I was wrong - it could come down to 7A...

 

[securespark]

Basically, 6mm should be adequate provided....it's not trunked-in along with other high-current cables.

Or trunked at all. If it is, the rating drops to 38A.

 

[ban-all-sheds]

Careful, securespark - diydoctor really get the hump if you dare to point out that their website is wrong - they regard it as slander.

 

[securespark]

Then I challenge them to back up what they're saying by referring to 7671.

 

[ebee]

"You should avoid that site like the plague - they lie to people about what the Building Regulations actually say because they think they know best what people can be trusted to know. "

I took a quick peek Ban,
I see what you mean about the untruths

 

[baz1968]

Careful, securespark - diydoctor really get the hump if you dare to point out that their website is wrong - they regard it as slander.

Is that why they banned you from there forum BAS? For telling them they were wrong and as usual your always right...