What Are the Reasons for Slow Cooling in Car Air Conditioning?
2 Answers
Here are the reasons for slow cooling in car air conditioning: 1. Insufficient refrigerant due to low levels. The primary cause of insufficient refrigerant is usually minor leaks in the system. If there is not enough refrigerant in the air conditioning system, the amount of refrigerant sprayed into the evaporator through the expansion valve will also decrease. Consequently, the heat absorbed during the evaporation of refrigerant in the evaporator will be reduced, leading to a decline in cooling capacity. 2. Moisture infiltration in the air conditioning refrigeration system. There is a component in the refrigeration system called the dryer (or receiver-drier), whose main function is to absorb moisture from the refrigerant to prevent excessive moisture from reducing cooling efficiency. However, when the desiccant in the dryer becomes saturated, it can no longer filter out moisture. As the refrigerant passes through the expansion valve's throttle orifice, the drop in pressure and temperature causes the moisture in the refrigerant to freeze in the small orifice, leading to restricted refrigerant flow, increased resistance, or complete blockage. 3. Reduced heat dissipation capacity of the condenser can also lead to decreased air conditioning cooling performance. Due to varying operating conditions, the condenser located in front of the car engine can become covered with oil, dirt, or debris, reducing its heat dissipation ability. Additionally, issues with the cooling fan, such as a loose drive belt, reduced fan speed, or high-speed problems, can also impair the condenser's heat dissipation. The solution is to clean the condenser surface with a soft brush and promptly address any fan malfunctions. 4. Other reasons include aging compressors and belts, clogged refrigerant lines, long-term neglect in replacing the air conditioning system's filter, and malfunctioning cooling fans. Furthermore, the quality of the car's window tint can also affect the cooling efficiency of the in-car air conditioning system.
A while ago, my car's air conditioning had a similar issue—it took forever to cool down. There could be several reasons, like insufficient refrigerant or a leak in the system that requires a recharge. If the fan speed is too low, the hot air can't dissipate, reducing cooling efficiency. Another possibility is a clogged cabin air filter or a dirty evaporator, which restricts airflow and prevents cold air from circulating. Compressor wear or aging is also common; performance tends to decline after a few years. I tried cleaning the filter myself, but complex issues really need professional repair—otherwise, driving in summer becomes unbearable and wastes fuel. Regular maintenance, like cleaning the evaporator annually, can help prevent such problems.
