What are the reasons why a car's air conditioning doesn't cool after running for a long time?
3 Answers
Reasons and solutions for air conditioning not cooling: 1. Insufficient or low refrigerant: A common reason for car air conditioning not cooling is insufficient or low refrigerant, likely due to minor leaks. The solution is to add refrigerant. However, note that if adding from the low-pressure side, do not invert the refrigerant bottle; if adding from the high-pressure side, do not start the engine. 2. Substandard refrigerant and refrigeration oil: Excessive impurities in the refrigerant and refrigeration oil can clog the car air conditioning's filter, leading to poor cooling. This increases resistance and reduces the flow of refrigerant to the expansion valve, resulting in insufficient cooling capacity. In such cases, it's essential to use qualified refrigerant for repairs, as it plays a crucial role in the car air conditioning system.
I noticed that the car air conditioning doesn't cool well after prolonged use, which is quite common, usually due to minor issues in the refrigeration system. The AC compressor may overheat, and continuous heavy workload can easily lead to failure. Additionally, if the refrigerant is insufficient or leaking, cold air won't be produced, naturally resulting in poor cooling. If the condenser is clogged with dust and heat can't dissipate, it will also affect the cooling performance. Loose fan belts or poor electrical contacts are other potential causes. I recommend taking breaks during summer drives to let the AC rest periodically, checking if the filter is clean to prevent minor issues from turning into major failures—otherwise, long trips could become quite uncomfortable.
I've been driving an old car for many years, and if the air conditioning is on for too long, it stops cooling. Most of the time, it's because the condenser is too dusty or the fan isn't spinning, leading to poor heat exchange. Also, if the refrigerant has aged and leaked, the pressure drops, and the compressor will stop working. Another factor is the evaporator frosting up, often due to system imbalance. I regularly use compressed air to blow out the condenser and remove debris to prevent issues. Driving for long periods in high temperatures can fatigue the components, so it's best to stop the car every couple of hours to give the air conditioning a break. Don't wait until it completely breaks down to fix it—that's both troublesome and costly.
