The function of the liquid receiver is to store the liquid refrigerant supplied to the evaporator. After the high-pressure refrigerant passes through the heat dissipation effect of the condenser, it becomes a gas-liquid two-phase state, but the refrigerant must enter the evaporator in a liquid state. Good cooling effect, so a liquid receiver must be installed behind the condenser to store the high-pressure refrigerant here, and then the liquid refrigerant drawn from the bottom is sent to the evaporator, so that the evaporator can play its best state. Achieve the best cooling effect.