Thermostats and mixer valves

Grohtherm 2000 exposed thermostatic bath/shower mixer

Shower mixer valves and shower thermostats blend the hot and cold water supplies and control the water flow to the shower head. Thermostatic valves are more expensive, however they offer a number of beneficial safety features in return for the additional cost.
 

Shower thermostats
For safety and comfort, a thermostat is an essential part of every shower. It allows you to pre-set a preferred water temperature and maintains it for the duration of your shower.
A thermostat will adjust the water supply to the shower within the fraction of a second should there be a change in the temperature or pressure of the supplied water – for example, if someone were to flush a WC elsewhere in the home.
A good thermostat will have a built-in safety feature to prevent the temperature for accidentally being raised above 38 degrees Celsius. Many also incorporate a diverter valve that allows you to switch between two shower outlets.

Water-saving features include Eco buttons that always start the shower at a reduced flow rate. These require the user to push a button on the control to increase the flow above a certain level, usually around 50 percent.
 

Shower mixers
Mixer vales work in the same way as basin faucets and can either be single control or dual control. They do not react to drops in water pressure or changes in temperature. 

Style and fixing choices
Thermostat and mixer valves can either be concealed (built-in) or exposed. With concealed models, the valve is located in the wall behind the tiles with only the controls and faceplate on show – this gives a clean, contemporary look. With exposed models the valve is externally mounted and connected directly to the shower hose.

Concealed models give you the freedom to locate the shower controls wherever you choose. If you are planning a large walk-in shower, then locate the controls close to the entrance. This way you can turn the shower on without getting hit by an initial rush of cold water.
 

Digitally-controlled thermostats
The latest development in showering is the introduction of digital thermostats. These are operated by remote control – unlike a conventional thermostat, where the controls and the valve are connected to one another – allowing you to locate the thermostat wherever you choose. Individual user buttons allow you to pre-set your preferred water temperature and flow rate. Wireless technology ensures that there are no electrics in the shower area.
 

Diverter valves
If you have more than one shower outlet (for example a handshower and a head shower) you will need a diverter valve. This allows you to divert the water between the two outlets. If you have a third outlet you may also require a stop valve.

The number of showerheads you can have working at once depends on both the water pressure and the volume of hot water available. For further advice consult your showroom.


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