Vimar RADIOCLIMA 01910 Instruction Handbook Manual page 17

CAUTION!
When the symbol flashes, the batteries are dying.
REPLACE THEM AS SOON AS POSSIBLE!
When the symbol is lit, the output relay automatically switches OFF.
REPLACE THE BATTERIES!
Programs and settings are not erased when the batteries are low or when changing them.
After replacing the batteries, the time and day of the week must be reset.