How to Install a Thermostatic Mixer Shower: An Ultimate Guide
Has your shower seen better days or maybe you’re looking to upgrade to a thermostatic model? You might be wondering if it’s possible to fit a new thermostatic mixer shower yourself.
While it may not be a straightforward DIY task, if you have some knowledge of showers and plumbing, you may be able to tackle this task yourself.
Keep reading for a detailed step-by-step guide to installing a thermostatic mixer shower.
Is a Thermostatic Mixer Shower Compatible with my Water System?
First, you’ll need to know what type of water system you have. The most common water systems are a high-pressure combi boiler, a low-pressure gravity-fed and an unvented system. It’s generally easy to tell what type of water system you have by the fittings in your house such as a combi boiler or water tanks in your loft.
However, the pressure of your water is also a good tell. For example, if your water pressure is low and gets worse when other appliances such as the washing machine, or dishwasher are turned on, you’ve most likely got a gravity-fed system.
Whereas, if you find your water pressure isn’t affected by someone flushing the toilet or turning the washing machine on, and you have a high-water flow, you’ll find you’ve either got a high-pressure combi boiler or an unvented system.
Once you know what type of water system you have, it’s time to find a compatible shower. The good news is most thermostatic mixer showers are compatible with both high-pressure combi boiler systems and low-pressure gravity-fed systems. If in doubt, it’s always best to check with a professional on the compatibility of a specific shower with your water system.
For more information on showers and shower systems take a look at the following video.
What Tools Will I Need?
Make sure to keep the following tools on hand throughout the process of installing your thermostatic mixer shower.
- Your new thermostatic shower (and other fittings included in the box)
- Instruction manual
- Adjustable spanner or wrench
- Screwdriver
- Spirit level
- Tape measure
- Detector (for identifying wiring)
- PTFE tape (optional)
- Pencil
- Electric drill and tile drill bit
- Pipe cutter
- Rubber mallet
- Old towel or sheet to mop up any water
Installing a Thermostatic Mixer Shower
Suppose you’re installing your thermostatic mixer shower from scratch and you're not fitting in place or an existing shower. In this case, you’ll first need to sort any pipework necessary for your new shower and connect this up to your hot and cold water feed. If this is something you haven’t done before, we suggest contacting a professional plumber as it isn’t a task for someone new to DIY.
However, if you’re fitting your new thermostatic mixer shower in place of an old or outdated model, or a professional plumber has sorted the pipework for you, keep reading for our handy step-by-step guide.
- First, you'll need to turn off the water supply. This is usually controlled by a stopcock, which can be found underneath the kitchen sink.
- Next, turn on both your hot and cold taps to release any water left in the pipes.
- If your shower came supplied with wall brackets, these should be fitted to the wall around your copper piping (15mm apart). To make sure the wall brackets are in the correct place mark where your screws will need to go and double-check before drilling. If you are drilling into tiles, make sure to use a tile drill bit to prevent any damage to the tiles.
- Once the holes have been drilled, you should insert a raw plug carefully into each hole. This shouldn’t be knocked in with a hammer as this could damage your tiles. Therefore, a rubber mallet is a good alternative.
- Place your wall covers onto the wall but don’t screw them in just yet. First, you need to check if you have any copper piping on show once the wall fixings are in place. If so, the copper piping should be cut back slightly to allow your new thermostatic valve to fit correctly.
- Mark the pipe just before the start of the wall cover and take the wall covers off. Now mark slightly closer to the wall than your previous mark. This new mark is where you should cut the pipe with your pipe cutter. However, be careful not to cut too far back as this can’t be undone. It’s always better to cut too little than too much.
- Now, you can fit the wall covers and screw in. Make sure to tighten the compression fittings to create a seal before adding your wall covers. The wall cover should simply screw on, hand tight, in a clockwise direction.
- Next, turn your water supply back on to flush out your pipes and remove any debris left. You may want to keep an old cloth, or towel nearby to mop up any water splashes.
- Make sure you’ve attached the rubber washers and filters, then you can start to screw in the valve. Tighten the valve hand tight before finishing off with your adjustable wrench or spanner. Be careful when tightening with your adjustable spanner as this could mark the finish of the valve. If in doubt use something simple like an old piece of cloth or kitchen towel to create a barrier between the valve and your spanner.
- At this stage it’s a good idea to check the valve is still level, using your spirit level. If so, you're ready to install your shower riser rail and handset.
- Firstly, fit the included brackets to ensure everything is fitted in the right direction. Once you’ve checked this, leave the brackets on as the next stage is preparing the wall to fit the riser rail.
- Next, you need to fit the small rubber washer into the bottom of the riser rail before screwing into the top of the shower valve until hand tight. This stage may vary if you have a shower with a handset and no overhead shower. If so, please refer to your shower's specific installation instructions.
- You now need to secure the riser rail to the wall. To ensure it is straight, use a large spirit level to line up the middle of your shower valve with the riser rail. Once you’ve found the right position, simply mark on the wall where you will need to screw and fit the connecting plate onto the wall. This process may differ slightly depending on the shower you’re fitting, therefore, it’s always best to consult the manufacturer’s instructions.
- Lastly, install your overhead shower by simply screwing in hand-tight to the top of your riser rail, ensuring it’s at the correct level for yourself or anyone else using the shower. If you have chosen a shower with a handset, this simply needs screwing into the hose and the other end of the hose then into the base of the shower valve.
- Once everything is fitted, it’s time to turn the water supply back on to ensure the system is working correctly, at the correct temperature, and water pressure.
- If everything is working correctly, congratulations, you have successfully installed a thermostatic shower. However, if you find anything isn’t working right at this stage, we suggest contacting a professional plumber to see what the issue is.
Explore Our Range of Thermostatic Showers
You've come to the right place if you’re in the market for a new thermostatic shower. Browse our website today to view our full range of thermostatic showers. With a wide range of both ceiling and wall-fed options, as well as thermostatic showers suitable for both high-pressure and low-pressure systems, we’ve got something for everyone.
If you found this post useful, you may also like - Thermostatic Shower Buying Guide – What are the Different Types of Showers? - The Causes of a Leaky Shower.
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