How to Remove & Replace a Thermostatic Shower Mixer Valve – Steam and Shower Cabins

So you are looking at replacing your thermostatic shower mixer valve on your steam shower, shower cabin or steam shower bath? 

In this guide we give you step-by-step instructions on removing and replacing the complete valve housing, additionally we have a video demonstrating everything you need to know to get you back up running in less than an hour so you can enjoy your steam or shower cabin again.

Before you get started you will need a few tools....

Tools Required to Replace a 2 or 3 Dial Shower Mixer Valve

  • Small Flat Screwdriver
  • Grips
  • Alun Key

The following step by step instructions will apply to pretty much all steam shower and shower cabins including Insignia, Aqualusso Opus and Alto, Lisna Waters, Vidalux, Aquaplus, Aqualine, Aqualux, Superior Spas and many more....Thanks to Insignia for this instructional video!

Step 1- Pull the cabin away from the wall with enough space to get behind, this is generally around 1 meter.

Step 2 - Isolate the water to the cabin, hopefully when the unit was installed you will have isolation valved behind the cabin.

Step 3 - Unscrew the cylinders from both the top & middle dials

Step 4 - Using an Alun key ( sometimes its a flat head screw) remove the grub screw from inside the dials, this is whats holding the dial to the valves.

Step 5 - Remove both the top and middle dials, these will simply pull off now, though they can sometimes be stuck due to limescale deposits, you can always spray some lime or lemon juice on these to loosen up.

Step 6 - Turn the Temperature dial fully round to the cold position, this will reveal a grommet that can be simply removed with a flat screwdriver.

Step 7 - As you did above, loosen the grub screw inside the dial and remove by pulling off.

Step 8 - Remove the securing nuts from the top and middle dials using grips or pump pliers ( Try and use a cloth to protect from scratching)

Step 9 - Next up remove the chrome faceplates from the top and middle dials, these will generally just pull off, though some models will be threaded ( note that in some cases there is silicone that has seeped through from behind and can slightly restrict easy removal.

Step 10 - Remove the plastic temperature safety lock from the bottom temperature cartridge, and make note of the position of this safety lock( take a snap with your mobile phone)

Step 11 - This is where you will need someone to go behind the unit and hold the valve for the final stage of removal. Simply unscrew the final faceplate and the valve should now be free to pull away from behind the cabin.

Step 12 - Disconnect all the hoses at the bottom of the valve. These will include the hot & cold water feeds (these are the metal braided hoses) If you have a steam shower, you will also have a 3rd hose that feeds to the steam generator. ( If hoses are not colour coded, again be sure to mark the hot and cold hoses accordingly)

Step 13 - Disconnect the top hoses, these are usually plastic/pvc material secured by either a jubilee clip or threaded connections which simply unscrew.

You are now ready to fit your new mixer shower valve, simply follow the instructions outlined above.