Gree LSQWRF35VM/NaA-M, Service Manual

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16
Unit Control
(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 electric 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 temperature 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 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.
(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 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.
(12) High-pressure sensor is used to detect the discharge pressure. When the detected temperature is
too high, control the compressor to regulate the frequency of discharge.