Electric Shower Designs
The majority of electric showers look remarkably similar: white plastic box on the wall, some control knobs on the front, shower hose linked to a spray head and slider rail kit. Although these showers look the same they can vary quite considerably in their performance and capabilities depending on the design features included in the unit.
The rating of the shower will vary from make to make and model to model. Higher kilowatt rating will mean a greater flow of water - see the following page for electric shower flow rates.
Most electric showers are designed with a power setting switch to enable the unit to cope with the variation in incoming water temperatures. Some will include a cold option where the flow restrictor is fully open and the heating elements switched off.
The phased shutdown feature that can be found on many showers is designed to reduce the chance of scalding. When an electric shower is switched off the heating elements will take a while to cool down. Water inside the heating chamber will be static and so it can get heated to very high temperatures quite quickly. If the shower is switched back on the first thing to come out of the spray head will be the scalding hot water. Phased shutdown is a feature of many electric showers that ensures that the heating chamber is cleared of hot water after the unit is switched off to prevent scalding.
The shower might not be the only appliance being used in a property that relies on mains water. If the shower is operating and somebody switches on a tap or flushes a toilet elsewhere in the home this can affect the pressure and flow of the water reaching the unit which will in turn affect the temperature of the showering water. An electric shower with a temperature stabilisation feature will attempt to regulate the water temperature in the event of a change of pressure. This is not a fully thermostatic control but does go some way to iron out temperature fluctuations.
There are some fully thermostatic showers on the market that will keep the water within 1 or 2 degrees of set temperature - such as the Mira Advance. If the shower is to be used by the less-able then a thermostatic electric shower, fitted with a lever control, would be the best option.
As customers have become increasingly design conscious electric shower manufacturers have made efforts to improve on the rather boring look of the basic shower. Some have opted for a chrome, glass or stone finish to the "box" while another option is to site the "box" remotely (in an airing cupboard or attic) with just a slim remote control panel visible together with the handset.