Low pressure sensor detects suction pressure during the cooling process. The control that controls the frequency of the compressor by the control method proportional to the operating capacity of the indoor units, so that the suction pressure is controlled within a suitable range.
If the suction pressure becomes too low, the small mass of circulating refrigerant may be insufficient for cooling the compressor and damaging the parts it composes.
Control: If the low pressure sensor output indicates vacuum and remains in the same vacuum condition for more than 12 minutes, the compressor will shut down to prevent damage to the system.