What is a Thermostatic Shower Valve

Posted by mprice 30/10/2017 0 Comment(s) Bathrooms,


Putting it simply, a shower with a thermostatic mixer valve ensures a constant water temperature is maintained while you shower.


Why do we need it?


We've all experienced it - having a nice shower, just got the water to a lovely temperature, then suddenly the water goes really hot or cold! Why - because someone in another room has turned a tap on or flushed the toilet.


A shower with a Thermostatic Mixer Valve gives precise control over water temperature and protects from any sudden changes in the water supply - no more hot or cold experiences! This also reduces the possibility of scolding making them an ideal choice for families with young or the elderly.


How do thermostatic shower valves work?


Thermostatic Shower ValveThe valve contains a thermostatic element which expands and contracts in response to changes in water temperature and pressure of both hot and cold water supplies. This expansion and contraction of the element moves a piston which controls the amount of cold and hot water entering the valve.


When the temperature increases and the element expands, the piston will move across the hot water inlet and open up the cold water inlet, which will decrease the temperature.


 A return spring ensures the opposite happens when the temperature decreases. This then allows less cold water in and more hot water in which will increase the temperature.


 Should the cold water supply fail, the element fully expands closing the hot water inlet completely preventing scalding hot water entering the valve.


What types of thermostatic shower valves are available?


There are many styles available but fall in to three main types:

  • Bar valve
  • Exposed valve
  • Concealed valve

Let's have a look at each in a little more detail.


Bar valve


This simple wall mounted valve offers a feed to the shower via a single hose outlet which is normally connected to a slider bar above. Simple to operate with an on/off flow dial on one end and a temperature control on the other end. 


This valve type is the most economical way of installing a mixer valve.




Exposed valve

 This valve type is similar to the above bar valve but typically offers supply to two outlets such as an overhead shower and a handset. Two dial levers operate the on/off flow and temperature control.


The dials and working are mounted externally to the wall hence the 'exposed' name.



Concealed valve


This valve, as the name implies, has the the workings of the mixer concealed from view, with only the dials exposed. As with the other valves, independent control is offered to the on/off flow and temperature.


This option offers a more sleek appearance but does mean that it is necessary to recess the workings in to the wall.




 We hope this gives an insight into the different types available, please have a look at our full range for further inspiration.

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