Why does the car air conditioner stop blowing air after prolonged use?
2 Answers
Car air conditioner stops blowing air after prolonged use due to the following reasons: Lack of refrigerant: Refrigerant loss is mainly caused by leaks. If the car's air conditioner is not cooling properly and stops cooling again after adding refrigerant for a while, you should be cautious. Generally, this situation indicates a significant issue. If the condenser is leaking, it needs to be replaced. To check for leaks, fluorescent dye is usually added to the refrigerant oil, and a specialized viewing glass is used to locate the leak points. Dirty condenser: The air conditioner condenser and radiator are located at the front of the car. When the vehicle is moving, air enters through the central grille, carrying debris such as fluff and leaves, which can accumulate on the air conditioner condenser and radiator.
My car always has this issue on the highway—after two hours of AC use, the airflow weakens significantly. Upon inspection, I found the evaporator coil frozen solid, blocking the vents. The mechanic said it's either a faulty temperature sensor or an overcharged refrigerant system freezing the pipes like ice popsicles. Now I've learned to switch to fresh air mode for a few minutes every half hour during long trips or raise the temperature by one degree. Ironically, this problem occurs less in winter but is worst when blasting cold AC in summer. Also, remember to check your cabin air filter—last time I replaced mine, it was completely clogged with leaves, which can reduce airflow even more than frost buildup.
