Showers Simplified

We have put together a simple guide to help you select the correct products for your bathroom, and to help you understand some of the terminology.

Plumbing systems & compatibility

Some taps require more specific requirements. Such systems are:

Gravity fed systems - hot and cold water tanks

Gravity / Mains systems - hot water cylinder and cold mains

Pressurised / Unvented Systems - as above but hot pressurised by cold mains supply

Pumped systems - gravity system with pump to boost water flow

Combination boilers - instant water heater (no hot/cold water tanks)

If you are in any doubt regarding your plumbing system see the Plumbing Systems Simplified information page.

Terminology

Mixer shower

Shower using both hot and cold water supplies to obtain showering temperature, generally give improved flow rates over electric showers. Can be used on any system providing water pressures are reasonably balanced and within recommended pressure range.

Electric shower

Shower requiring mains cold supply only, thus no requirement for stored hot water. The higher the rating the better the performance. A qualified electrician should be consulted during the wiring of these products.

Power shower

Showers using both hot and cold water supplies pumped from gravity fed systems to give high flow rates. Cannot be used with Combination or unvented mains systems.

Water pump

Used to create a power shower in gravity fed installations. Available in a variety of pressures to suit single shower or complete bathrooms. Integrated pumped shower mixers are also available. A qualified electrician should be consulted when wiring these products.

Manual mixer

Showers utilising ceramic disc cartridge with only one handle to control flow and temperature. This type of valve does not react to pressure or temperature changes in supply and is therefore manually controlled.

Pressure balancing mixer

Showers using a pressure sensitive cartridge giving added safety benefits when compared to manual mixer, again using only one handle to control flow and temperature. This type of shower provides a stable showering temperature despite fluctuations in supply pressures and also includes safety shut off upon failure of either supply.

Thermostatic mixer

Showers using a temperature sensitive cartridge giving further benefits when compared to manual and pressure balancing mixers, generally two handled control (dual control). Safety features include safety shut-off upon either supply failure or constant showering temperature upon fluctuations in supply temperature and pressure.

Sequential

Single handled thermostatic mixer shower. No control over flow, only on/off and temperature. Otherwise performs as above.

Recessed valve

Shower hidden within finished wall hiding all but operating handles and concealing plate.

Surface mounted valve

Shower fitted directly to finished wall with all parts visible. Supply pipes can be either exposed or concealed.

Fixed head

Shower head fixed to wall for use with concealed pipework and recessed showers.

Rigid riser

Showerhead fixed to wall with exposed pipework from valve for use with surface mounted showers.

Adjustable riser

Shower kit and handheld showerhead with height adjustment to suit varying user requirements.

Mechanical valve: Traditional type valve that uses a rubber washer to create a watertight seal.

Ceramic disc valve: Valve that uses hard wearing ceramic discs to create a watertight seal. Popular due to low maintenance and easy quarter or half turn action to operate.

Ceramic disc cartridge: Cartridge utilising cleverly made hard wearing ceramic discs to create taps with single lever operation. Becoming more popular due to low maintenance requirements and ease of operation.

Single flow: Hot and cold water mixes within the mixer body. To comply with Water Bylaws fittings such as this require single check valves fitted to each inlet.

Dual flow: Hot and cold water mix at the outlet of the tap, thus no check valves are required.

Check valves: Check valves (or Non Return Valves) are required to comply with Water Bylaws on certain fittings. They allow water to flow in only one direction. Please contact your local water authority for details.

Pressure reducing valves: Sometimes required on systems using mixers and with a high pressure imbalance. (greater than a ration of 5:1 generally)

Minimum pressure: Pressure required so that fitting performs adequately. Pressure depends on type of fitting and type of plumbing system installed. As a general guide, low pressure systems are gravity fed and less than 1.0 bar (1.0 metre vertical distance between shower outlet and base of cold water tank is approximately 0.1 bar), high pressure systems are mains fed, pumped or combination boilers.

Maximum pressure: Maximum safe working pressure. If this is exceeded all guarantees are void and fitting may get damaged.

Water Bylaws: All fittings must be installed to comply with these to ensure basic safety and legal compliance. Please contact your local water authority for details.

WRAS (Water Regulations Advisory Scheme): A product approval process whereby fittings are checked for mechanical reliability and material safety.

Don`t forget ? If you are confused or unsure in anyway why not post a question on our forum, after all that`s what we are here for. And there are plenty of plumbers and installers ready to give their words of wisdom and advice.

And, now for the legal bits - All information and details given within these pages are for information purposes only, Tap-advice.co.uk cannot accept any responsibility or liability for any preparation work that is undertaken based on such specifications or information shown on our site. We always recommend that you obtain advice from a suitably qualified plumber before making a purchase or arranging any installation. Remember it is always best to employ a professional to complete works.