Why does the car air conditioning stop cooling after running for a while?

[DelBeau]

The reasons why the car air conditioning stops cooling after running for a while are: 1. Clogged receiver-drier; 2. Faulty component in the air conditioning system; 3. Excessive refrigerant in the car air conditioning system; 4. Excessive moisture in the dryer; 5. Excessive dust on the filter screen; 6. Aging or loose belt; 7. Blocked air ducts or dirty air conditioning pipes; 8. Compressor failure. Solutions for the car air conditioning stopping cooling after running for a while include: 1. Timely replacement of the air conditioning receiver-drier and replenishment of coolant; 2. Cleaning the filter screen; 3. Checking the pipelines and air conditioning pump in the car air conditioning system for damage; 4. Inspecting the compressor.

[DelJanelle]

I've been repairing cars for over 20 years and often encounter situations where the AC stops cooling after running for a while. Insufficient refrigerant is a major issue—either it's leaking or depleted, requiring leak detection and recharge. When the cabin air filter gets clogged with dirt, airflow gets blocked just like having a stuffy nose. If the condenser is covered with bugs and leaves, it's like wrapping a blanket around a refrigerator, making heat dissipation impossible. Another common problem is a loose or broken compressor belt that prevents proper operation. Electrical issues are also frequent, such as malfunctioning temperature sensors sending wrong signals. My advice is to first rinse the radiator front, replace the air filter, and if that doesn't work, use pressure gauges to check refrigerant levels. Professional diagnosis is far better than random guesses—don't wait until complete failure when major repairs become costly.

[AylaFitz]

As someone who loves tinkering with cars, I've researched the issue of sudden AC failure. Last time, my car's AC was blowing cold initially, but after ten minutes, it felt like it wasn't on at all. Upon inspection, I found the cooling fan was stuck, causing the engine temperature to rise and triggering the AC protection shutdown. Another time, the condenser was clogged with poplar fluff, and it worked fine after rinsing it with a water gun. Refrigerant leaks are hard to spot—check for oil stains on the pipes. I remove and clean the AC filter every month to prevent dust from clogging the vents. Also, watch out for a buzzing noise from the compressor—it could indicate internal wear. During regular maintenance, ask the mechanic to check the expansion valve; if it's clogged, you're in trouble. After parking in the sun, rolling down the windows to let heat escape before turning on the AC improves cooling efficiency.

[McCorey]

Having driven a taxi for over a decade, my old Jetta's AC has had all sorts of issues. It's common for the AC to blow warm air after half an hour of driving, mainly due to aging pipe seals leaking refrigerant. If the radiator fan relay burns out, the system shuts down—just touch the fan to check if it's hot. A faulty thermostat switch is the worst; it thinks the temperature is fine when you're roasting inside. Once, the expansion valve froze and blocked the pipeline, but stopping roadside for a while restored cooling. Remember to change the filter regularly—I replace mine every 20,000 km without fail. If the AC stops cooling, turn it off immediately to prevent the compressor from dry running and seizing. A roadside shop can check refrigerant pressure for just twenty bucks—don't push your luck driving with a faulty system.