Understanding Shower Valves

Understanding What a Shower Valve Doesdiverter switches between one of three outlets. In
A shower valve is that part of the shower whichaddition a diverter has an off position which cuts the
controls the flow and mix of hot and cold water intosupply of water to all the showers outlets. Diverters
the rest of your shower. It does this using ado not supply water independently to the shower
combination of diverters, flow controls andoutlets, only one can be on at a time. In addition
temperature controls.diverters do not allow fine control over the rate of
How does it do it - Diverters, Flow Controls andflow, although there may be some control each
Temperature Controlsoutlet is basically full on or full off.
Temperature ControlThermostatic and Manual Shower Valves
All valves usually have a single temperature control.Thermostatic shower valves include an inbuilt
The temperature control varies the proportion on hotanti-scald safety mechanism which cuts off the flow
and cold water that is mixed allowing theof water if the temperature of the mixed water
temperature of the resultant mix to be controlled.exceeds a (usually) pre-set value. Some thermostatic
Once the water has been mixed by this part of thevalves also allow the water temperature to be set
valve various flow controls and/or diverters thenand maintained, but this is rare, most thermostatic
direct the mixed water to the various functions ofvalves just provide an automatic safety cut off
the shower. (By function we mean any of themechanism. Manual valves do not provide this safety
shower outlets, e.g. overhead shower, slider rail, bodyfeature.
jets etc.In general a shower will be supplied water from the
Flow Controlsame mains system and boiler as all the rest of the
A flow control is simply a valve controlled by a handleplumbing in the house, this means that changes in
or lever on the valve. It takes water that has alreadywater usage in other parts of the house can effect
been mixed by the valve and restricts its flow fromthe flow of water to the shower and more
full off to full on allowing fine control of the rate ofparticularly can cause a reduction in the supply of cold
flow between these two extremes. Each flowwater to the shower. This results in the mixed water
control generally controls the rate of flow from abeing delivered by the shower containing a higher
single valve outlet and from there to a single showerproportion of hot water meaning that the water
function. To control a shower with two functionstemperature rises. Its in just such situations that
such as an overhead shower and a hand held showerthermostatic valves protect the use of the shower
one option is to use a shower with two flowfrom injury.
controls, each flow control independently controls theExposed and Concealed Shower Valves
rate of flow to a single outlet, this means that youGenerally showers can be classed as exposed or
can have both controls on at the same time, this is inconcealed. A concealed shower is one where most of
contrast to diverters (see below).the pipe work associated with the shower is fitted
Diverterinside the wall and in particular the shower valves
A diverter is a switch used to direct water that hasshower outlets are inside the wall. An exposed
already been mixed in the valve to one of two orshower by contrast has a shower valve with outlets
more valve outlets. A two way diverter switcheson the outside of the wall and the pipe work
water between one of two outlets and a three waysupplying the various shower functions are visible.