Air in the system can also lead to insufficient cooling. Once the air enters the air conditioning system, the pressure of the refrigeration pipeline will be too high, or the refrigerant circulation will not be smooth, which will also lead to insufficient refrigeration, mainly due to poor sealing of the refrigeration system or incomplete vacuum pumping during maintenance.
Too little refrigerant leads to insufficient refrigerant. Most of the reasons are slight leakage of refrigerant in the system. If the refrigerant in the air conditioning system is insufficient, the refrigerant injected into the evaporator from the expansion valve will be reduced accordingly, resulting in the reduction of heat and refrigeration capacity absorbed by the refrigerant when it evaporates in the evaporator.
Of course, it is not better for cars to drive at high speed, because the speed is fast and the pressure of air conditioning system is high, the compressor will stop working because the pressure controller is too high, and the refrigeration will also be suspended. Therefore, in the daily maintenance of vehicles, it is also necessary to regularly replenish cooling liquid to the air conditioner and clean the filter screen to avoid excessive dust accumulation on the filter screen and affect the operation.