Airflow and the Condenser
The condenser receives high-pressure, high-temperature vapor from the compressor. It releases this heat into the cooler air, passing through its fins. When idle, ram air is reduced and replaced by airflow from the engine's cooling fan. It's essential to maintain airflow through the condenser at stoplights. If the cooling fan is inoperative, airflow is restricted, and air conditioning performance is affected.
This reduced airflow is typically the result of a faulty fan clutch or a faulty electric fan motor or circuit. Road debris clogs and damages the condenser's fins, reducing its ability to exchange heat. Cleaning and straightening the condenser's damaged fins restores airflow through the condenser.
As shown in the illustration, the condenser and the radiator are close. Air flows through the condenser and the radiator. An overheating engine reduces the condenser's ability to function, and many PCMs prevent compressor clutch operation if the engine is overheating.