Why does the car air conditioning system show no leaks under pressure?
3 Answers
No leaks under pressure occur because the precision of high-pressure gas charging for leak detection in the air conditioning system is insufficient. Here are the relevant explanations: 1. Check the high-pressure valve core: Since low-pressure evacuation is generally performed. Press the high-pressure valve with your finger to see if there is a suction sensation. If no issues are confirmed, then the only remaining possibility is the compressor oil seal leak. Due to current environmental standards, the structure of compressor oil seals should be understood. Therefore, there will be no leaks under pressure, but leaks may occur during evacuation. 2. Car air conditioning: Used to adjust and control the temperature, humidity, air cleanliness, and airflow within the car cabin to optimal conditions, providing a comfortable environment for passengers and reducing travel fatigue; creating good working conditions for the driver and playing an important role in ensuring safe driving as a ventilation device. It generally includes refrigeration devices, heating devices, and ventilation devices.
I often see this situation in the repair shop. The car's air conditioning system holds pressure without any leaks, mainly because the entire system is tightly sealed without any gaps. For example, the hoses, connectors, and compressor seals are all intact, showing no signs of corrosion or aging. When pressure testing, professional tools are used, and the pressure remains stable after being set, indicating that the refrigerant isn't leaking from anywhere. Typically, this happens when the car is well-maintained or has newly replaced parts. However, it's important to note that a leak-free system doesn't mean the air conditioning is problem-free—if the cooling effect is poor, it could be due to internal compressor blockage or insufficient refrigerant. Therefore, I recommend regularly checking the air conditioning system and performing a pressure test before each summer to identify potential issues early. This is closely related to maintenance habits; frequently replacing wear-prone parts can save a lot of trouble.
I just performed an air conditioning pressure test on my car, and there was no leakage at all. The reason is quite simple—it's probably because I replaced all the seals and tightened every connection myself last week. I used a borrowed pressure gauge for the test, set the value, waited for 10 minutes, and the pressure didn't drop, indicating the system is well-sealed. This means there are no cracks in the components and the hoses haven't aged. However, I once encountered a leak before, but it was fixed and never happened again. If there's no leakage but the AC still doesn't cool, you should check if the refrigerant level is insufficient or if the compressor is faulty. Overall, no leakage is a good sign, reflecting proper maintenance. I recommend car owners learn how to perform simple pressure tests—the tools aren't expensive, and DIY saves time and effort. Regular checks can also extend the AC's lifespan, so don't wait until something goes wrong to panic.
