What happens if a car AC filter is dirty?

If the car air conditioning filter is not replaced for a long time, the accumulation of impurities such as dust and pollen will reduce its filtration efficiency, directly affecting the air quality inside the car and exposing passengers to harmful substances like bacteria and mold. This may cause allergies or respiratory discomfort, especially having a greater impact on children and the elderly with weaker immunity. From a mechanical perspective, a clogged filter will force the air conditioning system to operate at higher power to maintain normal air volume, leading to increased energy consumption and reduced cooling efficiency. In addition, microorganisms growing on the filter will spread through the air outlets, producing odors and further affecting driving and riding comfort. It is best to replace the filter regularly every 10,000 kilometres or annually. If the air output weakens or there is a noticeable odor inside the car, the filter should be checked and replaced immediately. Regular maintenance not only ensures a healthy breathing environment but also optimizes the performance of the air conditioning system, avoiding high maintenance costs caused by neglecting minor issues.