Grohe SENSIA IGS Notice D'utilisation page 264

OPERATING INSTRUCTIONS
Pull the controller out straight, without twisting it. Release
the battery cover by rotating to the left and pull it straight out.
Remove the old battery and dispose of it correctly. Fit a new
CHANGE BATTERY
battery, making sure the polarity is correct.
1. Remove controller
2. Unscrew cover
3. Replace battery
–
+
Reverse the disassembly procedure above to put the parts
back together.
Please dispose of the old battery correctly. It may not be
disposed of with household waste.
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