As summer temperatures soar, the air conditioning system of a car becomes one of the most relied-upon features. However, many drivers encounter issues such as weak cooling, reduced airflow and unpleasant odors. These symptoms often indicate underlying faults or neglected maintenance issues. This article provides a clear guide to identifying common air-conditioning problems and how to properly maintain your system for optimal comfort and safety.

Common Car AC Issues

Poor cooling performance, weak airflow, or unpleasant odors from a car's AC are usually caused by the following issues:

Refrigerant Leak or Low Level：

Refrigerants are the key substances that transfer cold energy in air-conditioning systems. If the system leaks or evaporates excessively, it will weaken or even completely disable the cooling function.

Compressor Malfunction：

The compressor is the power core of an air conditioning system. Once a mechanical failure or belt slippage occurs, the air conditioner will not be able to operate normally.

Clogged Cabin Air Filter：

When the filter element becomes clogged with dust, it obstructs airflow, causing a decrease in air volume and the growth of odors, which can seriously affect passenger health.

Moldy Evaporator：

In a humid environment for a long time, mold can build up on the evaporator, causing a musty smell and reducing the efficiency of the air conditioning system.

Regular Maintenance Tips

Routine maintenance extends the life of the AC system and improves the in-cabin air quality. The following are key maintenance tips and recommended intervals:

Replace Cabin Filter：

Replace every 10,000–15,000 km; replace earlier if the environment is dusty. We recommend using an activated carbon filter cartridge to enhance odor removal and filtration.

Clean the Evaporator：

It should be cleaned once every 1–2 years, especially in humid regions or when there are frequent odors inside the car.

Check and Recharge Refrigerant：

The system pressure should be checked every 2–3 years. If there is a noticeable lack of cooling, replenish the system and immediately check for leaks.

Fan and Duct Inspection：

When airflow is weakened, check whether the fan or air outlet is blocked or whether the motor is worn out.

 Usage Tips for Health and Efficiency

In addition to regular maintenance, daily usage habits play a key role in performance and hygiene.

◎Turn off the A/C a few minutes before parking, leaving only the fan on to help the evaporator remove moisture and prevent mold growth.

◎Avoid using the “internal circulation” mode for extended periods. Switch to the “external circulation” mode as appropriate, to ensure air circulation.

◎Turn off the A/C a few minutes before stopping the engine to allow the blower to dry the evaporator. Avoid prolonged use of the recirculation mode to ensure fresh air intake. Regularly check for unusual noises or leaks.

A well-functioning car AC system depends on timely maintenance and appropriate use. If you experience weak cooling, bad odors, or poor airflow, it may be time to check for refrigerant leaks, clogged filters, or moldy components. With the right care, your vehicle’s air conditioning system will remain clean, efficient, and reliable all year round.

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