However, an unhappy experience a decade or so ago with one of the early instantaneous electric showers need not deter you from having a modern one installed today. There have been some tremendous advances in design and construction and you can be confident that a modern model will work properly provided that it is properly installed according to the manufacturer’s instructions. Most instantaneous showers must be supplied with water at a minimum pressure of 1.05kg per sq cm (l5lb per sq in). They are intended for connection direct to the mains supply, though they can be supplied by a cistern if it is at least 1 O.75m (35ft) above the level of the shower spray. In most cases mains water pressure will be adequate, but those who live in an area where mains pressure is low should check the actual pressure with their local water authority before incurring the expense of installation. Fitting a shower Modern electric showers usually have an electrical loading of 6kW to 7kW and it is often possible, for the sake of economy, to switch to a low setting of 3kW or 4kW during the summer months Choose a model that incorporates a temperature stabilizer. This is an anti-scald device that maintains the water temperature at the level chosen by the user of the shower, despite any fluctuations in pressure which may result from water being drawn off from taps or by flushing the W.C. Should there be a drop in pressure beyond the capacity of the stabilizer, a safety sensor turns the shower off completely.
When choosing your instantaneous electric shower, look for evidence that it has been approved by such national safety committees as the B.E.A.B., the National Water Council and the ANT. (Assessment of Techniques) Committee of the Institute of Electrical Engineers. Fitting A Shower Although instantaneous electric showers can be fitted over a sit-down bath, they are usually installed in a separate shower cubicle which may be in a bathroom, in a bedroom or even on a landing. The shower tray must have a trapped outlet and the branch waste pipe can discharge by the same route as basin or bath wastes. Plumbing connections should be straightforward. It’s best to connect the supply pipe to the shower heater first and then work backwards to the main supply, making this connection last of all. In this way you will interrupt the supply to the rest of the house as little as possible. The connection to the shower may be a simple compression coupling or it may have a screwed male thread. In which case you’ll need a compression fitting with a coupling at one end and a female screwed connector at the other. To connect into the rising main you should use a compression tee.Obtaining the power
Instantaneous showers get their power from a separate radial circuit taken from the consumer unit. As most models of shower have a loading of either 6 or 7kW they can be supplied safely by a circuit that has a current rating of 30A and is run in 6mm2 two-core and earth cable. Recently, however 1 an 8kW shower has been introduced on the market by some manufacturers. This shouldn’t pose extra problems for anyone intending to install it: provided the radial circuit originates at either a cartridge fuse or MCB—which both have the effect of uprating the circuit by one third — then a 30A circuit will be adequate. Should you decide to install one of these larger showers then it’s still probably a good idea to check their requirements with the makers beforehand. Showers should be controlled by a 30A double-pole cord-operated switch. From this a length of 6mm2 two-core and earth cable will run to the shower unit. There is one type that requires a slightly different method of connecting up. If you’re going to fit a shower that has a control unit already connected to a length of three-core flex then you’ll have to fix a flex outlet unit on the wall near the shower unit so you can connect the flex into the circuit.read more