Danfoss RET M Instructions D'installation page 13

Thermostat status (cool mode only)
A snowflake symbol will be lit whenever the thermostat is calling
for cooling. If this is seen to flash, the thermostat output is delayed
for a short period to prevent compressor damage.
RET M-LS model only
When set to "O" the thermostat output is turned off and "Of" is
displayed.
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This model is fitted with an Auto/Off switch.
When the switch is set in "I" position the
thermostat controls at the temperature set by
the setting dial.
GB
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