Sound of compressor equipment: When using cold air, under normal circumstances, the compressor only produces a "stuck" sound at the moment when its electromagnetic clutch is engaged or disengaged, and it should be extremely quiet when running. If there is a "rumbling, rumbling" sound during operation, it means that the compressor may be worn due to the lack of refrigerant oil in the pipeline. Solution: Generally, only a new compressor can be replaced;
Belt noise: Usually, the belt driving the compressor is not tight enough and slips after the compressor is loaded, resulting in a sharp whine. It can be improved by tightening or replacing a new transmission belt;
Fan noise: There are two kinds of fans here, one is the auxiliary fan behind the water tank to help cool the refrigerant, and the other is the blower to transport cold air. If their motor bearings are worn, the noise will increase with the increase of speed. It is recommended to replace the fan or lubricate the blower bearing;
Wind direction and noise of hot water valve. When the operation panel key is used to adjust the temperature, the hot water valve of the engine cooling water flowing into the heat exchanger is controlled; When the air outlet angle position is adjusted, the duplicate valve for controlling the wind direction will act. These parts may make some noise when moving. If the air conditioning system belongs to the electronic constant temperature control type, this kind of noise may also appear when the engine is not started, which is a common abnormal sound in the center console. If it is not serious, it can be ignored. Otherwise, you can go to 4S, request to connect a computer, and reinitialize and set the voltage value of the related motor with 505 1 or 5052 software.
Second, there is insufficient refrigeration.
Insufficient refrigerant: refrigerant is a medium that absorbs heat. If the refrigerant in the pipeline is not filled for a long time, the pipeline leaks, air is mixed, and the amount of refrigerant in the system is insufficient, which will lead to insufficient refrigeration. When using cold air, you can check the amount of refrigerant in the pipeline from the transparent window on the storage tank. If you see many bubbles in the window, it means that the amount of refrigerant is not enough. In addition, if the refrigerant is overfilled, it will lead to insufficient refrigeration and increase the possibility of pipeline leakage. It is recommended to supplement or vacuum leak detection, and fill with refrigerant and compressor oil with standard pressure after repair;
Compressor does not operate: the working cycle of refrigerant in the pipeline must rely on the transmission of compressor. If the compressor cannot run due to abnormal refrigerant pressure, line failure, temperature sensor damage or compressor electromagnetic clutch burning, the refrigeration is insufficient. It is recommended to replace the temperature sensor or electromagnetic clutch;
Poor heat dissipation of the condenser-the refrigerant compressed by the compressor is a high-temperature and high-pressure gas, which can only be changed into a low-pressure and low-temperature liquid refrigerant through cooling by the condenser and decompression by the expansion valve, and finally reaches the evaporator to absorb the heat of the carriage and evaporate. If the cooling effect of the condenser (located in front of the water tank) is not good, such as: the auxiliary fan is not running and the condenser radiator is blocked by dirt, which will cause poor liquefaction of the medium and reduce the refrigeration capacity;
The refrigerant line is blocked. This happens most often in liquid storage tanks or expansion valves. It is suggested to clean the pipeline, vacuumize the refrigerant again and replace it with new products;
Air output is too small. The air filter screen is blocked, resulting in too little air blown out of the air outlet, which makes the driver feel that the cooling is not enough. In addition, many drivers always like to adjust the coolness to the coldest, the wind speed to the maximum, and then reduce the air volume when it is too cold or too windy, and rarely adjust the temperature, so they only rely on the air volume to control the temperature. This will lead to the situation that the exit is extremely cold and the car is not cold, which is easy to cause the frost and fog blown out of the air outlet to freeze the evaporator. It is suggested to replace the air conditioning pollen filter. Generally, the temperature can be set to 2 1 degree, and the AOTU mode can be used for operation;
Mixed heating. If too much heat is mixed in when cold air is needed because of the failure of the cold and warm adjusting plate, it will cause insufficient cooling. This situation can be judged from two phenomena: first, when the car is cold, the air conditioner is hotter than when it is cold; Second, the refrigerant low-pressure pipe in the engine room (usually thick in diameter and covered with heat insulation material) is extremely cold, but the cold air is not cold. It is recommended to check and replace the duplicate motor of the warm air distribution pipe; Check and eliminate computer control faults.