Robertshaw Smart Sense Series Installation Manual page 31

TT = OC: A closed contact on the TT terminals will switch the thermostat to
Occupied Mode, where the temperatures for functions OC and OH
will replace the user set temperatures. See page 43.
TT = DA: The thermostat will broadcast the measured temperature from
the remote temperature sensor via ModBus. It will not display this
value on the LCD, nor is it used for any control option. This mode is
intended to provide system feedback to the ModBus master only.
TT = 2P: The function is intended for controlling a two pipe fan coil. The
mode of the thermostat (heating or cooling) will be determined
solely on the temperature as measured by the remote sensor. The
remote sensor (SMART-R-03) is typically strapped to the fan coil
water supply line. The mode button only permits the user to select
OFF or ON, where ON is either heat or cool mode based on the
remote sensor temperature.
AF=0 ANTi-FReeze FuNCTiON
AF = 0: Anti-freeze function OFF
AF = 1: Room temperature will not be permitted to fall below 41ºF (5ºC)
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