Gree A Series Service Manual page 19

A Series Modular-type Air-cooled (Heat Pump) Chiller
(5)An entering water temperature sensor is used to detect the temperature of the entering
water which will determine whether to start or stop the compressor and the auxiliary elec-
tric heater. When this sensor fails, all compressors of the unit will stop.
(6)Defrost temperature sensor is used to detect the liquid tube temperature of fins serving
the condenser, which will determine whether to start the fan. When the sensed tempera-
ture is too high or this sensor fails, the control board will detect and send this signal to the
display. Then, the display will tell there is an error and the unit will stop or will not start.
(7)An anti-freezing and overheating prevention temperature sensor is used to detect the
water temperature. When it fails, compressors and fans of the corresponding unit will stop.
(8)A leaving water temperature sensor is used to detect the leaving water temperature.
When this sensor fails, compressors and fans of the corresponding unit will stop.
(9)An air temperature sensor on shell-and-tube heat exchanger is used to detect the air tem-
perature. When this sensor fails, the compressor in a cooling state will have to be stopped
and the display will tell there is an error. If the sensor fails in a heating state, only the dis-
play will tell an error.
(10)An liquid temperature sensor on shell-and-tube heat exchanger is used to detect the
liquid temperature. When this sensor fails, the compressor in a cooling state will have to
be stopped and the display will tell there is an error. If the sensor fails in a heating state,
only the display will tell an error.
(11)A suction temperature sensor is used to detect the suction temperature. When this sen-
sor fails, the compressor in a cooling state will have to be stopped and the display will tell
there is an error. If the sensor fails in a heating state, only the display will tell an error.
(12)High-pressure sensor is used to detect the discharge pressure. When the sensed tem-
perature is too high, control the compressor to regulate the frequency of discharge.
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