What Causes Car AC Not Cooling in Summer?

[Penelope]

AC not cooling is due to insufficient refrigerant, dirty condenser, or water in the pipelines. Insufficient refrigerant: Refrigerant loss is mainly caused by leakage. If your car's AC underperforms and worsens again after refrigerant recharge, pay attention. A relatively simple method to detect leaks is to check for oil stains on the condenser surface through the grille—this usually indicates condenser leakage. Dirty condenser: In summer, poor AC performance often leads to 4S shops recommending radiator cleaning. Cleaning the radiator and condenser aims to improve heat dissipation. When cottonwood or willow catkins clog the condenser, it causes engine overheating or AC malfunction. During cleaning, always use an air gun first to blow away debris before water washing; otherwise, it may backfire, worsening AC performance and increasing fuel consumption. Water in pipelines: The car AC refrigeration system has a dryer tank to absorb moisture from the refrigerant. When the dryer's desiccant becomes saturated, moisture can no longer be filtered. As refrigerant passes through the expansion valve orifice, pressure and temperature drop, causing water in the refrigerant to freeze in the small hole. This obstructs refrigerant flow, increases resistance, and prevents the AC from cooling.