New Teana 2.0 travels 10,000 kilometers, and the air conditioner does not cool. What's the problem?

It's very hot now, and I find that the air conditioner doesn't cool. The wind is not cool, what's the matter? The master pointed out that the weather is hot now and found that the air conditioner is not cooling. The wind is not cool, what's the matter? Expert advice 1. Sensory test method: 1. Compressor running status: whether the drive belt is broken or loose. If the drive belt is too loose, it will slip, accelerate wear and can't transmit power. Whether there is noise inside the compressor. Noise may be caused by internal parts damage, and internal wear cannot be effectively compressed. Whether the compressor clutch slips. 2. State of condenser and fan: Is the condenser heat sink covered with dust? If the condenser fins are covered with dust, the efficiency of the condenser will be greatly reduced. Whether the condenser fan works well. 3. The running state of the blower fan makes the fan run at three speeds: low, medium and high. If there is abnormal sound or the motor is not working well, it should be repaired or replaced, otherwise the air supply flow is insufficient. 4. Check the amount of refrigerant. If you see a lot of bubbles through the observation window, it means that the refrigerant is insufficient. If water is poured on the condenser to cool it, there is still no foam in the observation window, indicating that there is too much refrigerant. Check the joints and connections of all devices for oil pollution, which indicates that there is refrigerant leakage, and relevant parts should be reinforced or replaced. (Leak detector can be used to detect leaks) 5. Whether the HVAC valve or thermal windshield is closed, and whether other windshields are adjusted normally (note: if the compression clutch cannot be engaged, the blower fan cannot be operated, and the condenser fan cannot be operated, etc. First, check related electrical systems, such as relays, sensors, open circuit or short circuit, control unit, etc. ). Second, the instrument detection method This method uses a complete set of snow pressure gauges to find the fault location. First, turn off the switches at the high-pressure end and the low-pressure end of the pressure gauge, connect the refrigerant filling hose to the corresponding maintenance valve of the compressor in the shutdown state, and exhaust the air in the hose by using the refrigerant pressure in the refrigeration device. At this time, the readings at both ends of the high and low pressure should be in a balanced state.) Start the engine, maintain it at 150rpm, set the speed of the blower at the highest gear, and set the cold air at the maximum position, in a "recirculation" state. The normal reading is: 1 at the low pressure end and the high pressure end. The indicated values of pressure gauges on the high pressure side and the low pressure side are lower than the standard values, and bubbles can be seen through the observation hole. Cause: air leakage in refrigeration cycle; Refrigerant is replenished irregularly. Treatment method: use leak detector to detect leakage, repair and replenish refrigerant. 2. The pressure gauge on the low pressure side indicates negative pressure, and the indicator on the high pressure side is lower than normal. There is a temperature difference between the pipes before and after the liquid storage tank/dryer. In severe cases, the pipeline behind the storage tank/dryer is frosted. Cause: the expansion valve or low-pressure pipeline is blocked, and the storage tank/dryer or high-pressure pipeline is blocked; The expansion valve pressure bubble leaks and the needle valve is completely closed. Disposal: Remove or replace related parts and liquid storage tank/dryer. If the pressure bubble leaks, replace the expansion valve. 3. The indicated values of pressure gauges on both sides of high and low pressure are higher than the standard values, and the exhaust side of the condenser is not hot. Cause: Overfilling of refrigerant. Treatment method: discharge excess refrigerant to make the pressure reach the standard. 4. The pressure gauges on both sides of the high and low pressure are higher than normal, but the pressure on the high pressure side drops sharply to about 2kg/cm2 after shutdown. Cause: air is mixed in the refrigeration cycle (insufficient evacuation or air enters during filling). Treatment: refill with time. If the above symptoms persist, replace the oil tank/dryer and compressor oil. 5. The pressure gauges on the high and low pressure sides all indicate that it is higher than normal, and the pipeline on the low pressure side is frosted or deeply condensed. Cause: the expansion valve failed (the needle valve was opened too wide); The expansion valve pressure bubble is disconnected from the evaporator. Solution: Check and reconnect the pressure bubble or replace the expansion valve. 6. The low pressure side pressure is high, and the high pressure side pressure is low. After shutdown, the pressure on both sides tends to balance immediately. Cause: The compressor valve, piston or piston ring is damaged and cannot be compressed effectively. Solution: Replace the compressor. 7. On both sides of low pressure and high pressure, the indicated value of pressure gauge fluctuates. Cause: Because the dryer is supersaturated, the moisture in the refrigerant can't be removed, which makes the needle valve in the expansion valve freeze and causes ice blockage. When the refrigerant is no longer circulating, the ice is thawed by the circulating heat and then frozen into ice, and the process is repeated. Disposal: Replace the storage tank/dryer and compressor oil, and re-vacuumize and fill. The reason why the automobile air conditioner is not cooled is 1: lack of refrigerant. Generally, automobile air conditioners will add refrigerant snow once every 2-3 years. Some cars even have a very big picture of the owner once a year. Is the refrigerant flowing in the car? Why do you have to add it often? Isn't the air conditioner sealed? Moreover, according to the fact that air conditioning refrigeration is a physical reaction, there is no need to lose too much refrigerant, so it is gone. In fact, the air conditioner seal is very tight, but it can't stop the refrigerant from flying, and there is a slight leak in the air conditioner pipeline or condenser. The loss of refrigerant is mainly leakage. If the air conditioner of your car is not good and the refrigerant starts to break down after adding it for a while, then you should pay attention. This usually happens, mostly because of the rhythm of bleeding. If the condenser leaks, it needs to be replaced, and the method of checking the leakage is also troublesome. Generally, it is necessary to add fluorescent agent to fluorine oil and check it with special glasses to find out where the dew point is! There is also a relatively simple method, which is suitable for the case that the condenser surface is wet by oil through the middle net when the leakage is serious. In this case, the condenser usually leaks. 2. Damage to the air-conditioning damper The failure of the air-conditioning damper motor is rare and not unheard of. If there is something wrong with the flap motor, it will be in trouble. Generally, the flap motor is located under the instrument panel and belongs to the main switch of the air outlet of the air conditioner. If it is broken, the switch is broken. Even if the air conditioner can cool the cold air, it can only come out of the gap, which means drinking medicine to quench your thirst. When you turn on the air conditioner and find that all the air has left the air, you should be careful. Replacing the flap motor requires disassembling the instrument panel, which is a huge project. The condenser is dirty in summer, and it is often found that the air conditioner is poor. There is no problem in the air conditioning system test, and the high and low pressure are basically normal. When you go to a 4s shop to repair a car, you will often recommend the owner to do an activity of cleaning the water tank. The purpose of cleaning the water tank and condenser is mainly to dissipate heat. Catkin stuck on the condenser in spring will cause the engine temperature to be too high or the air conditioning to be poor. So every time after the spring, car owners must check whether there are many Mao Mao pasted on the water tank. When cleaning, be sure to blow it clean with a blow gun first. Cleaning with a water gun will be counterproductive, not only increasing the bad fuel consumption of air conditioners. 4. The air conditioner compressor, throttle valve or expansion valve is damaged. There is a saying in the compressor circle of air conditioner that "low pressure is high, high pressure is low, and the compressor should be changed". I didn't know it was summed up so brilliantly by my predecessor. The probability of air conditioning compressor damage is not great, so don't care too much. As for the failure of expansion valve and throttle valve, it directly leads to poor air conditioning. These inspections are complicated and need to be repaired by professional repair shops. 5: The belt is too old and loose. I checked all the equipment of the air conditioner and found nothing wrong. What's the problem? In fact, the belt is also a relatively neglected component. Generally, the 4s shop will remind you to change the belt during maintenance. If it is not replaced, it will slip in the use of the project, resulting in belt breakage, abnormal sound of the belt, no electricity and poor air conditioning. Therefore, it is necessary to check the engine belt. 6. There is a drying tank in the automobile air conditioning refrigeration system, and there is water in the pipeline. Its main task is to absorb the moisture in the refrigerant and prevent the cooling capacity from decreasing due to too much moisture in the refrigerant. However, when the desiccant in the drying tank is saturated, water can no longer be filtered out. When the refrigerant passes through the orifice of the expansion valve, due to the decrease of its pressure and temperature, the moisture in the refrigerant will freeze in the orifice, resulting in poor circulation of the refrigerant, increased resistance or no flow at all, resulting in the inability of the air conditioner to cool. There are many reasons why the air conditioner is not cold, such as the failure of the temperature sensor in the car and the failure of the outdoor temperature sensor. There are many small reasons that cannot be found out. Don't worry if the air conditioner is broken. Excluding the above six points, there will be basically no problem. @20 19