What are the reasons for a car air conditioner not cooling properly?
3 Answers
There are several reasons why a car air conditioner may not cool effectively: 1. Excessive refrigerant: Too much refrigerant can reduce cooling efficiency. If the refrigerant and compressor oil contain excessive impurities, minor blockages can occur, leading to insufficient cooling capacity. 2. Insufficient refrigerant: A lack of refrigerant results in inadequate cooling. A dirty condenser or a loose compressor drive belt can also cause the air conditioner to blow warm air. 3. Excessive impurities: If the refrigerant and compressor oil contain too many impurities, minor blockages can form, reducing cooling capacity. If the entire air conditioning system has excessive contaminants in the refrigerant and compressor oil, the filter screen will likely become clogged, decreasing refrigerant flow, increasing resistance, and reducing the amount of refrigerant reaching the expansion valve, thereby causing insufficient cooling.
When the car air conditioning is not cooling, common reasons may be that the air filter is clogged with dust accumulation blocking the cold air; or refrigerant leakage causes the system to lack refrigerant and fail to cool; compressor failure, loose belt, or internal wear prevents cold air from being produced; the fan not rotating leads to poor heat dissipation, causing the entire system to fail; electrical system issues such as relay fuses blowing and cutting off the power. I suggest first checking the filter yourself and replacing it with a new one for convenience. If it still doesn't work, test the refrigerant pressure and seek professional repair if necessary—don't push through driving in high temperatures as it's dangerous. Regularly cleaning the condenser to prevent dust buildup can also help.
When the car's air conditioning fails to blow cold air, it is often due to insufficient refrigerant caused by leaks at pipeline connections or the evaporator; the compressor is stuck and cannot operate normally, producing a buzzing sound; the condenser surface is dirty, clogged with dust or insects, reducing heat dissipation efficiency; a fan circuit failure causes the fan to stop, leading to heat buildup and insufficient cooling; electrical issues such as faulty temperature sensors or poor switch contacts make the system mistakenly believe it is set correctly, while the actual output is insufficient. I prefer using professional tools to diagnose high and low-pressure systems, addressing issues early to avoid compressor damage and costly overhauls, ensuring safe and comfortable driving.
