Sinclair SDV 6 User & Installation Manual page 23

Sleep: After sleep is enabled, the home page will show a sleep icon.
The sleep function is only applicable to cooling and heating modes
and unavailable for auto, dry and fan modes.
With sleep enabled, it will be cancelled after manual power-off or
mode switching. You have to re-enable this function.
Sleep mode is not supported on FAPUs.
Auxiliary heat source: The auxiliary heater has four modes:
Auto Operation of Auxiliary Heater, Auxiliary
Heater Enabled, Auxiliary Heater Disabled, and
Auxiliary Heater Used Separately.
Auxiliary heat source
can only enabled in
Heat mode
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