How to Install a Concealed Thermostatic Shower

What You'll Need
Pipe cutters
Tape measure
Dust sheets
Adjustable wrench
Tile Drill
Spirit Level
Thermostatic shower mixer
Connecting shower head
Plastic and copper pipe (15mm)
Plastic and copper connections (tees and elbows)
Shut-off valves

A concealed thermostatic shower is equipped with an automatic adjuster, a device that controls the temperature of your shower. For example, if someone flushes a toilet in a downstairs washroom while you are showering in the upstairs bathroom, the adjuster will ensure that your hot water won’t suddenly turn to scalding hot rather than comfortably warm. Installing a concealed thermostatic shower is similar to installing taps, but the mixer is installed on the wall rather than on the tub. They don’t need electrical connections, but work by mixing hot and cold water together within the cylinder. However, for this type of shower to work successfully, you must have the large levels of stored hot water available. If you discover that your system does have water pressure of at least 0.5 bar, you’ll be able to install the concealed thermostatic shower. 

Step 1 – Decide On Location 

First, you’ll have to decide where you will be drawing your hot and cold supply from. If you’re fitting the thermostatic shower above a tub, then you can tee into the supplies available for the taps. If not, you can tee into the closest hot and cold pipes. 

Step 2 – Turn Off and Drain out 

Turn off your stopcock and then turn on the hot and cold faucets to drain any water out of the pipes. 

Step 3 – Tee In 

Tee into your hot and cold supplies, running the pipes toward the shower. If you use pipe inserts at the joints of your plastic pipes, they’ll help you to avoid deterioration. As close as you can to the shower, include shut-off valves on each of the hot and cold supply. At the end of your plastic pipes, slot in copper pipes and at the end of those, put in plastic stop ends. After you turn the spigot back on, check for any leaks. 

Step 4 – Flush 

Thermostatic shower valves can incur damage if there is any dirt in the water coming through them. You can avoid this damage by flushing the new pipes. Make sure the water is off, remove the plastic stop ends and after finding a helper to hold buckets under the outlets, turn the water back on. When you’ve completed flushing, shut the water off again. 

Step 5 – Mark and Cut 

Place the shower valve over the outlet pipe so that you can mark your pipe to allow the shower valve to sit flush to the wall. Cut both of the outlet pipes. 

Step 6 – Drill 

Mark the location and drill your holes for your thermostatic valve. 

Step 7 – Use an Olive 

Place an olive into each inlet on your shower valve and tighten the retaining nut with one turn. 

Step 8 – Align 

Line the shower pipe up with the supply pipes. Make sure they fully slip into the inlet pipes. Screw the valve to the wall before tightening the retaining nuts with your adjustable wrench. Make sure your shower tap isn’t turned on before turning the stopcock back on to check for leaks. 

Step 9 – Connect the Hose 

If your thermostatic shower kit has a flexible shower hose, connect it and fit the shower head bracket in place. For a solid riser pipe, cut it down if needed (they come with enough length to fit different ceiling heights) with a pipe saw. Measure carefully. When fitting the riser pipe into place, use your level. Mark for the top-bracket mounting holes, drill and plug them. 

Step 10 – Fit in the Riser 

Install the riser, securing the nuts on the top and bottom. If your kit has an extension piece for your shower head, mount that and then put on the shower head. Turn on the shower to check for leaks. To test the thermostat, switch on taps or flush toilets to see if your shower temperature stays constant.