Electric Showers Do’s and Dont’s

Although they are classed as easy to install, go anywhere showers, electric showers should always be installed by a Part P-certified plumber or electrician, as they’ll understand the electrical engineering necessary for such work.
You should always choose an installer who is a member of a self-certification scheme such as those listed below. To get more details of these competent person schemes from your local council’s Building Control department
BRE Certification – 0333 321 8811
British Standards Institution – 0845 076 5606
ELECSA – 0333 321 8220Electric Showers
NAPIT Certification – 0845 543 0330
NICEIC Certification Services – 0870 013 0382

Make sure that your installer will take responsibility for ensuring the installation complies with the building regulations and will provide the BS7671 certificate. You will need to produce this if you want to sell your home to prove that electrical work has been carried out safely

An electric shower requires plumbing only to a mains cold water supply with 15mm diameter pipe.

The electrical supply is more complicated, however. The high-power electrical element (between about 8.5kW and 10.8kW) is similar to that of a large kettle, heating the water as it passes through.
Electric showers are generally between 8.5kW and 10.8kW

It will require connection to a separate fused electrical supply circuit. The size of the cable and fuse will depend on the electrical power (in kW) of the shower, but 10mm2 cable is recommended, as this would mean you can replace the shower in the future without having to install a larger cable.

For safety, you’ll need a ceiling-mounted double pole switch (with neon and mechanical indicators) to turn the electricity supply to the shower on and off.
Follow these instructions and you will be assured of safe, comfortable showering for many years to come.