What are the reasons for the Nissan Sunny Classic's air conditioning not cooling?

[Paisley]

Here are the reasons why the Nissan Sunny Classic's air conditioning does not cool: 1. The air conditioning filter is too dirty, leading to reduced airflow and poor cooling performance; 2. Insufficient refrigerant in the compressor. Cars used for more than 5 years should have their compressor refrigerant checked promptly; 3. Poor heat dissipation from the radiator or condenser. If they are too dirty, it can cause the engine to overheat. Here are four common reasons why a car's air conditioning does not cool: 1. Long-term use of the external air circulation mode: External air circulation draws in outside air through the condenser, while internal air circulation recirculates the air inside the car through the condenser. If external air circulation is used for a long time, it directly draws in hot outside air, resulting in poorer cooling performance compared to using internal air circulation. 2. The air conditioning filter is too dirty, reducing airflow: The air conditioning filter is designed to filter out impurities from the air in the system. Over time, it can become clogged with dust, pollen, leaves, or even insects, leading to reduced airflow and poor cooling performance. It may also produce unpleasant odors. 3. Insufficient refrigerant in the compressor: If the above two reasons are ruled out, it is necessary to check whether the air conditioning compressor has insufficient refrigerant, especially for cars used for more than 5 years, as they may have refrigerant shortage issues. 4. Poor heat dissipation: The radiator and condenser are crucial components for heat dissipation in a vehicle. If they are too dirty, heat dissipation will be poor, which not only causes the engine to overheat but also directly affects the cooling performance of the air conditioning system.

[Kenneth]

Speaking of the Xuan Yi Classic's AC not being cold enough, I've been driving this car for several years and have encountered similar issues. The most common problem is insufficient refrigerant, which can leak over time, especially in older cars where the seals have aged, preventing cold air from coming out. Another issue is a clogged AC filter—too much dust buildup can affect airflow and cooling efficiency. I always recommend checking it during maintenance. Also, check if the cooling fan is working properly. In the summer, when driving at high speeds, a faulty fan can cause the condenser to overheat, making the AC ineffective. Compressor issues are also common; if you hear strange noises or nothing at all, it’s likely due to a loose belt or internal damage. Regular AC system inspections can prevent these problems—don’t wait until summer when driving becomes unbearable. Safety first—if the AC fails, it can lead to fatigue and distraction, so get it checked by a professional shop right away.