If you’ve ever been blasted with cold water during a shower, you’ll know it’s a rude awakening.

A thermostatic mixer shower can help you make your showers so much more of an enjoyable experience because they ensure that you get the water temperature you want without a fuss.

What’s a thermostatic mixer shower?

A thermostatic mixer shower makes use of a device that mixes hot and cold water so that you have a constant stream of it at the exact temperature you want.

Here’s what you should know about thermostatic mixer showers. Let’s start by exploring how thermostatic mixer showers work.

How Do Thermostatic Mixer Showers Work?

How Do Thermostatic Mixer Showers Work

When hot and cold water enters the valve of the mixer, their temperature is set to one that you’ve previously selected on the mixer.

A thermal-sensitive device located inside the valve will automatically choose the correct amounts of both hot and cold water based on your preferences. This prevents spikes in water supply, pressure, and temperature.

Of course, nothing’s perfect and things can happen. If there’s a supply failure of cold water, the thermostatic mixer’s device will block the flow to prevent very hot water from being allowed and burning you.

The same goes for hot water supply problems. The device will shut down the flow of water so you don’t experience a blast of ice-cold water!

Within a few seconds, the device will regulate the water and deliver it at the temperature you want so you don’t have to fiddle with taps to get the temp you want halfway into your shower.

Another important feature you should know about thermostatic mixer showers is that they store water at a hot temperature before it gets mixed with cold water so they don’t rely on an internal heating system in the case of electric showers.

What To Know About The Thermostatic Mixer Shower Valve

Thermostatic Mixer Shower Valve

The thermostatic mixer shower valve contains several parts that work to make your showers better. Here are more details about the valve components and how they work to correct and adjust the water temperature.

  • Thermostatic element. The most important part of the valve is the thermostatic element, which is sensitive to the water temperature as it flows. It increases or decreases in size.
  • This is what the thermostatic element is attached to, and it works in the following way: when the thermostatic element increases in size when the temperature of the water gets hotter, the piston moves over the entry portals where hot and cold water enter, therefore reducing the amount of hot water and increasing the cold water, so that you get the water temperature you want.
  • Return spring. When the thermostatic element decreases in size because there’s less heat in the water, the return spring will move the piston back over the entry portals, this time to increase how much hot water is there and decrease the amount of cold water.
  • Temperature control. This is a dial that you will use to either increase or decrease the amount of heat in your water. When you use this dial, it moves the piston.

What Are The Pros And Cons Of Thermostatic Mixer Showers?


  • Thermostatic mixer showers do all the hard work for you to ensure that you get water at the right temperature every time, throughout your shower.
  • They’re safe for use by the whole family, especially children and the elderly, because of how they prevent water from being too hot.
  • You can add a pump to the mixer shower if you want more water pressure, such as if your water pressure at home is low.
  • Thermostatic showers look exactly the same as regular showers. Their only difference is that they have a thermostatic valve to mix hot and cold water together before it reaches you.
  • Thermostatic valves are constructed out of metals like chrome and brass, which increase their lifespan and make them durable.
  • You can find thermostatic mixer showers for baths. These look like regular combination taps but they have thermostatic valves inside them. They work the same for baths as they do for showers.


  • These types of showers do require regular maintenance to prevent common issues. These include intermittent cold and hot water.

How To Adjust Your Thermostatic Mixer Shower

How To Adjust Your Thermostatic Mixer Shower

Making small adjustments to your thermostatic mixer shower is easy and can prevent issues such as intermittent cold and hot water. Here’s what you need to do.

  1. Start by unscrewing the shower’s handle or lever. You’ll see a grub screw. In case you’ve never worked with grub screws before, it helps to know that these screws vary from other types of screws because they don’t have a protruding head.
  2. This screw needs to be loosened with an Allen key so that you can pull the handle off the shower’s valve.
  3. Remove the brass temperature stop lug. You’ll have to remove the retaining screw that’s fitted on the end.
  4. Put on the flow control and test the water. If the water’s coming out too cold, you’ll need to turn the brass spindle in an anti-clockwise direction until you find the temperature you want. On the other hand, if the water is coming out too hot, you’ll need to turn it clockwise.
  5. When you’ve found the correct water temperature, simply turn off the water flow with the use of the handle and put all the parts back.

What To Do If There’s Limescale On Your Thermostatic Mixer Shower?

Many appliances and fixtures can be a target of limescale, that white chalky scum that forms as a result of minerals in hard water.

Luckily, it’s really easy to clean limescale from your thermostatic mixer shower valve – and you don’t need to buy any special product.

Here’s how to do it.

  • Remove the valve. Note that the valve could be concealed or exposed depending on the style of the mixer.
  • Place it in a solution of one-part white vinegar and one-part water. You should leave it in this solution for 30 minutes.
  • When that time is up, rinse the valve and replace it.
  • If you can still see some limescale on the valve after doing the above steps, you will have to try to use a stronger solution – opt for pure vinegar and let it soak in it for the same amount of time.

Types Of Thermostatic Mixer Showers

There are various styles and designs of thermostatic mixer showers to choose from so you can find the perfect one to complement the size and design of your current bathroom. Here’s a rundown of them.

  • Bar shower design. A bar shower valve is small and compact, so it’s ideal for smaller bathrooms. Bar shower valves are in the shape of a bar, hence their name, and they’re the most budget-friendly out of all thermostatic mixer showers.
  • Concealed shower design. This valve is ideal for minimalist bathrooms because it features a plate behind which all the components of the shower mixer are located. You only see the riser, showerhead, and controls so you don’t have to worry about having a chunky fitting on the wall.
  • Exposed shower design. The complete opposite of the concealed shower, the exposed mixer shower has all the controls and shower components in full view so you can customize your shower. For example, you can change over from using an overhead shower to the shower handset. This type of thermostatic mixer shower is best for larger bathrooms.
  • Traditional shower design. If you like classic bathroom designs, this traditional shower mixer offers traditional touches such as cross handles and it has exposed valves.

Related Questions

Related Questions About Thermostatic Mixer Showers

What’s the difference between a thermostatic mixer shower and a  mixer shower?

These are similar to each other, but a thermostatic shower pulls water from the home’s existing supply and has a thermostat to maintain the water temperature.

A mixer shower, on the other hand, also mixes hot and cold water but it can’t make adjustments if there’s a change in temperature.

Can you install your own thermostatic mixer shower?

You can definitely go the DIY route when it comes to installing your thermostatic mixer shower. PlumbWorld has easy instructions on how to go about it so you save money on installation costs.


If you want more enjoyable showers without the stress of trying to get the perfect water temperature, you should consider purchasing a thermostatic mixer shower.

In this article, we’ve looked at this shower type’s pros and cons, as well as provided you with information to help you maintain your shower in the best way, such as when it comes to making adjustments to it so shower time becomes your favourite part of the day.


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