What Causes Car AC to Freeze and Stop Blowing Air?
2 Answers
The reasons why a car's air conditioning freezes and stops blowing air include: 1. Clogged AC filter: This prevents airflow, leading to freezing. 2. Blower motor failure: A damaged blower motor stops the AC from blowing air. 3. Issues with the car's AC control system: For example, a faulty expansion valve with excessive opening can cause the evaporator temperature to drop too low, resulting in ice blockage and preventing airflow. Detailed analysis of why a car's AC freezes and stops blowing air: 1. Clogged AC filter: When the AC operates, outside air passes through the filter before entering the car, trapping many airborne particles and easily becoming clogged. You can remove the filter to check if it's too dirty—excessive dirt can block airflow. 2. Blower motor failure or damage: This will inevitably stop the AC from blowing air. Overheating of internal coils or capacitor damage can cause blower motor issues. You can test by setting the AC to maximum speed and listening for the blower motor's sound to determine if it's faulty. If a fault is detected, promptly visit a 4S shop or repair facility for inspection and repair.
There are several main reasons why a car's air conditioning system may freeze and stop blowing air. An imbalance in refrigerant is a key issue; for example, overcharging or undercharging the refrigerant can cause the evaporator temperature to drop too low, leading to rapid freezing and blockage of the air ducts. A faulty thermostat can also cause the cooling system to run continuously, failing to detect temperature rises and stop the cooling process in time, ultimately resulting in freezing. A clogged air filter reduces airflow, causing cold air to linger near the evaporator and accelerate freezing, which is particularly common after prolonged use of the AC. Fan system failures, such as motor damage or stuck fan blades, can also reduce airflow and promote freezing. If not addressed promptly, this issue can lead not only to a lack of airflow but also to excessive heat inside the car, affecting driving comfort and safety. It is recommended to check the AC's sound after parking or replace the filter regularly. If freezing occurs, turn off the AC and wait for the ice to melt before troubleshooting. If the problem persists, it is best to visit a professional repair shop for a comprehensive check of the refrigerant and electronic systems.
