What Causes the Passat's Air Conditioning Not to Cool?
2 Answers
Possible reasons for the Passat's air conditioning not cooling could be too much or too little refrigerant, excessive impurities in the system, or air in the air conditioning refrigeration system. Here is a detailed explanation: Too much or too little refrigerant: Both excessive or insufficient refrigerant can cause the car's air conditioning to fail to cool. This is because the proportion of refrigerant volume in the air conditioning system has specific requirements. If the proportion is too high, it can affect heat dissipation, meaning more heat dissipation results in greater cooling capacity; conversely, less heat dissipation leads to reduced cooling capacity. If there is insufficient refrigerant in the system, the amount of refrigerant sprayed into the evaporator from the expansion valve will decrease, and the heat absorbed during evaporation in the evaporator will also decrease, resulting in lower cooling capacity. Excessive impurities in the system: If there are too many impurities in the refrigerant and refrigeration oil throughout the air conditioning system, the filter screen of the filter will become clogged, reducing the refrigerant's flow capacity and increasing resistance. This leads to a relative decrease in the amount of refrigerant flowing to the expansion valve, causing insufficient cooling capacity. Air in the air conditioning refrigeration system: If air enters the air conditioning system, it will cause excessive pressure in the refrigeration pipes, poor refrigerant circulation, and similarly result in insufficient cooling.
Last year when I was driving my Passat, I encountered an issue with the air conditioning not cooling properly. It was so hot that I was sweating profusely while driving. Possible causes included insufficient refrigerant—just like a car 'lacking air,' the compressor would stop working. Another reason could be the condenser being clogged with dust, preventing heat from dissipating. Sometimes, it's just a dirty air filter blocking the airflow, and a simple cleaning would fix it. Later, I realized that parking in the shade to avoid direct sunlight can protect the components, saving both money and hassle. After taking it to the repair shop, it turned out to be a loose compressor connection, and a quick replacement solved the problem. Regular maintenance can prevent such issues—don’t wait until summer to rush for repairs, as it wastes time and affects driving comfort.
