Electric Shower

BaronFox · Posted: Wed Dec 13, 2006 4:18 pm Post Subject: Electric Shower

Hi, I have a 8.KW Triton Amber from Homebase that is only giving out cold water?
I therefore bought an 8.5kw Triton Ivory as a replacement. Will it work, I have checked the fuse board and its either a 6am, 20am or 30amp fuse, the cabling looks like 6mm.

didthathurt · Posted: Wed Dec 13, 2006 4:21 pm Post Subject:

Or none of the above? An 8kW shower would draw about 34Amps so why do you think it is one of these 3 fuses? If it is, the answer could be in the question, it doesn't work because the fuse has blown. Who is to fit this shower and are they aware of the need for supplementary earth bonding?

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BaronFox · Posted: Wed Dec 13, 2006 4:43 pm Post Subject: Electric Shower

Many Thanks for your prompt reply, I can assume it must be the 30amp one, but the 8kW Shower lasted for over 4 year so I assumed the element is knackered rahter than thinking it was the cabling as the fuse boars is within 18 metres to the shower.

Can i simply just change the amp for the shower to 40 amps and the 8.5kw will work,

or the old one 8kw may still work ?

didthathurt · Posted: Wed Dec 13, 2006 5:27 pm Post Subject:

Do not insert a 40 Amp fuse into the existing circuit.

This much power has to be handled with extreme care. To change the 30 Amp fuse to a 40 Amp fuse could be dangerous and could lead to an electrical fire. Also, certain CU's will only accommodate a fuse of a max rating of 30Amps. If you can post a picture of your CU or give a full description of it, any makers marks, the colour, how many fuses in it, any unused fuse carriers (be our eyes for us), one of us may be able to go a bit further with you.

Upon changing a shower like this it is required, by law, for the person changing it to ensure that the wiring is up to the job, that the CU is - including the presence of an RCD (the regs require all equipment to be installed iaw the manufacturers instructions - and they all say an RCD is required) - and that the bathroom is correctly fitted with earth bonds. It is not a straightforward question, though, at first glance, it might appear so. For example a 6mm cable may be able to safely carry a max load that can vary from 29Amps to 51 Amps depending on how and where it is sited between the CU and the shower. In a normal domestic situation, this range reduces to between 32 and 46Amps. Your 8.5kW shower will need about 37Amps.

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Steve · Posted: Wed Dec 13, 2006 10:15 pm Post Subject:

4 years is a good innings for a shower in this day and age. However, have you tested there is power getting to the unit? is there a light that comes on?

Inspect the wiring in the pullcord switch, and report your findings.

An 8.5kw shower will work ok on a 30 amp fuse (it might never blow), however the fuse will run warm, and it sounds like an old fusebox, so please dont attempt this.

When was the last time your electrical installation was inspected? It may be worthwhile having a periodic inspection done now. This will take a few hours and cost you around £100-150. It will give you a ull breakdown of the state of the wiring, and highlight any faults that need urgent non-urgent remedial work.

Since you appear to have an old Wylex box, I highly recommend in inspection, as its unlikely you have RCD protection and supplementary bonding in the bathroom (both are potentially life-saving things, and are usually required by shower manufacturers if they are to honour any warranties)