Bosch Greensource SM024 Installation, Operation And Maintenance Manual page 36

36 | System Protection
Fig. 56 Condensate Overflow Sensor Location
Discharge Air Temperature (DAT) Sensor
The DAT sensor is installed at the inlet attached to
a motor mount (leg) and connected to the HPC. It
reads the supplied air temperature to determine
whether the unit is operating in the correct state
according to the thermostat demand. The DAT
works together with the Return Air Temperature
(RAT) sensor to determine if there is a heating/
cooling fault. These faults will appear on the
monitor interface when paired with the Bosch
EasyStart app. Location of the DAT Sensor is
shown in Fig. 57.
Fig. 57 DAT Sensor Location
8733819578 (2019/02)
Return Air Temperature (RAT) Sensor
The RAT sensor is installed in front of the filter
(bottom-right corner) and connected to the HPC. It
reads the RAT to determine whether the unit is
operating in the correct state according to the
thermostat demand. The RAT works together with
the DAT sensor to determine if there is a fault
either Not Cooling, Heating with Cooling Demand,
Not Heating, or Cooling with Heating Demand. This
information will appear on the monitor interface
when paired with the Bosch EasyStart app. The
factory location of the RAT is shown in Fig. 58.
Fig. 58 RAT Sensor Factory Location
Proper operation of the unit requires field
modification of the RAT sensor by removing the
sensor from the provided clip, drilling a ~1/4" hole
12"–18" from the evaporator coil in the ductwork,
and securing the RAT sensor in this hole for the
most accurate RAT readings as shown below in
Fig. 59.
Fig. 59 RAT Sensor Field Location
Subject to change without prior notice
Greensource CDi Series SM
Greensource CDi Series SM Model