What are the reasons for poor cooling effect in sedans?

[AryaLynn]

The reasons for poor cooling effect in sedans are: 1. Reduced heat dissipation capacity of the condenser; 2. Long-term closure of the internal circulation switch; 3. Refrigerant leakage, insufficient pipeline pressure; 4. Blocked air ducts, excessively dirty air conditioning pipelines; 5. Blocked dryer or expansion valve; 6. Aged or loose belts; 7. Presence of water in the pipelines. The solutions for poor cooling effect in sedans are: 1. Clean the condenser; 2. Repair or replace the compressor; 3. Add air conditioning refrigerant; 4. Adjust the belt tension. The maintenance methods for car air conditioning are: 1. Choose an appropriate air conditioning temperature; 2. Control the direction of the air outlet; 3. Avoid prolonged operation; 4. Avoid smoking when using the air conditioning; 5. Avoid using the air conditioning at low speeds; 6. Turn off the air conditioning before shutting down the engine.

[DeBeau]

I recently encountered the same issue with weak AC performance, making summer drives unbearable. It's most likely due to insufficient refrigerant, just like a fridge running low on Freon. During my last maintenance, I found the condenser fins completely clogged with willow catkins and insect remains, cutting heat dissipation efficiency in half. If there's a leak in the AC lines or the compressor belt is worn out, cooling efficiency will plummet. Special reminder: don't randomly recharge refrigerant - older cars' seals are prone to failure. Remember to check the cabin air filter too. My three-year-old car's filter was clogged like a facemask, reducing airflow and cooling. Regular radiator cleaning and filter replacement can actually prevent 80% of AC issues.

[StAllison]

With over a decade of experience in auto repair, I've found that the most common issues with malfunctioning air conditioning boil down to these three pitfalls. If your car's AC works fine for the first two years but starts cooling poorly by the third year, it's likely a slow refrigerant leak—getting a pressure test at a reputable shop is the way to go. If you notice strange odors or unusual noises when the AC is on, there's an 80% chance leaves are jammed in the blower motor or a mouse has made its home there, and cleaning it out is a real hassle. Another often-overlooked problem is the AC evaporator. I've seen many owners who never clean it, leading to mold buildup that blocks the air ducts, preventing cold air from circulating effectively, which naturally makes the AC seem weak.

[OKarter]

When I used to drive an older sedan, I noticed a pattern: the more the AC ran in traffic, the hotter it got, and it only cooled down on the highway. This is caused by poor circulation in the cooling system. If the cooling fan's RPM is insufficient or the relay is faulty, the condenser turns into a hot water kettle at red lights. Moisture in the AC lines can also freeze and cause blockages, often manifesting as sudden loss of airflow from the vents. I recommend checking the cooling fan's operation and having a technician measure the AC's high and low pressures—data is far more reliable than perception.