Mark the position of the new unit on your bathroom wall, including where the four new screw holes should be drilled. Then use a drill with a masonry bit to drill these holes, insert wall plugs, and screw the new unit on.
Refer to the manufacturer’s instructions to connect the water supply and the electrical cables. If at any point you are unsure about these connections, consult a professional.
Replace the cover of the unit, ensure dials align with the spindles, then screw the cover in place.
If you are also fitting a new shower hose, shower head and slide bar, now’s the time to mount and connect these.
When you are fully confident that your electric shower is properly installed, turn the power and water supply back on, test that it works, and enjoy your new shower!