What Are the Reasons for Poor Cooling in Large Vehicle Air Conditioning?
2 Answers
The main reasons for poor cooling in large vehicle air conditioning are: 1. Too much or too little refrigerant: In the air conditioning system, the proportion of refrigerant has specific requirements. Too much or too little can affect the cooling performance. If there is too little refrigerant, the amount sprayed into the evaporator by the expansion valve decreases, leading to reduced cooling capacity. Conversely, too much refrigerant can affect heat dissipation, as more heat dissipation results in greater cooling capacity. 2. Clogged filter: Vehicle air conditioners are equipped with air filters to block impurities. If not cleaned or replaced for a long time, accumulated impurities can clog the filter, preventing cold air from flowing out and reducing cooling efficiency. 3. Compressor damage or aging: The air conditioning compressor is a crucial component for normal operation. If the vehicle is older and the air conditioning fails to cool, the compressor may have issues like looseness or aging, affecting transmission efficiency and leading to poor cooling. First, check if the drive belt is broken, then listen for noise inside the compressor. 4. Damage to the air conditioning compressor, throttle valve, or expansion valve: The likelihood of compressor damage is low, so it’s not a major concern. However, faults in the expansion valve or throttle valve directly cause poor air conditioning performance. These checks are complex and require professional repair services.
The other day, the air conditioning in my truck suddenly stopped cooling. It took me a while to figure out the reason. The most common issue is refrigerant leakage—truck AC lines are long and prone to aging and leaks. Another common problem is a clogged AC filter. Trucks running long distances collect a lot of dust; last time I cleaned mine, the filter was caked with mud. Radiator fins clogged with willow catkins or insect carcasses blocking airflow also cause trouble—I ran into that last summer. Faulty electric fans with insufficient speed are another frequent issue, especially in older vehicles with aging wiring. Slipping compressor belts or faulty compressor solenoid valves are also annoying, and these all require a professional mechanic to diagnose. My advice: clean the radiator fins monthly and replace the filter quarterly—it’ll save you a lot on repairs.
