What are the reasons why the air conditioner does not cool?

Air conditioner cooling failures are frequent in summer. According to data from home appliance repair platforms, reports of air conditioners failing to cool in July and August account for 45% of the annual total. Most failures can be resolved through basic troubleshooting. Below is a summary of the five core causes and corresponding solutions.

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Abnormal refrigerant is the primary cause, accounting for 35% of all failures. Refrigerant leakage leads to frosting on the thin pipe of the outdoor unit and higher air outlet temperature, mostly due to aging pipes or poor sealing of interfaces during installation. For air conditioners used for more than 5 years, fluoride pressure should be tested once a year. If a leak is found, professional personnel are required to repair the leak before adding fluoride in quantitative amounts. Avoid blind refilling, which may cause secondary damage.

Clogging of the air circulation system is also common. Long-term failure to clean the filter screen will accumulate dust, reducing air intake by more than 40%. Frosting on the evaporator affects heat exchange efficiency. Users can clean the filter screen by themselves weekly. If the air output is still weak, check whether the evaporator is dusty. It is recommended to ask a technician to clean it with a special cleaning agent once a year.

Electrical component failures require careful handling. A non-starting compressor is mostly due to capacitor aging, characterized by the outdoor unit being inactive while only the indoor unit blows air. Such failures require replacing the capacitor with the same model. A malfunctioning thermostat will cause a discrepancy between the set temperature and the actual temperature, requiring professional calibration or sensor replacement. Do not disassemble it by yourself.

Incorrect mode operation accounts for 12% of cases, especially among new users who easily mistake "dehumidification" or "fan" modes for cooling. During troubleshooting, first confirm the mode setting. In cooling mode, the temperature should be set 2-3℃ lower than room temperature, and the "ventilation" function should be turned off to reduce cold air loss.

Environmental factors can also restrict cooling efficiency. Direct sunlight on the outdoor unit or surrounding clutter can reduce heat dissipation efficiency by 25%, leading to a sudden drop in cooling effect during high noon. Installing a sunshade and keeping a 50cm clearance around the outdoor unit, along with closing curtains to reduce heat sources, can improve cooling efficiency by 15%.

Industry insiders suggest that three checks should be done before using the air conditioner: check the filter screen, check the mode, and check the status of the outdoor unit. In case of abnormal compressor noise or pipeline freezing, stop the unit immediately and contact after-sales service to prevent minor faults from worsening. Regular maintenance can extend the cooling lifespan of the air conditioner by 3-5 years, making summer use more hassle-free.