How to Determine if a Car is Low on Refrigerant?

[DavidFitz]

Methods to determine if a car is low on refrigerant are as follows: Method 1: After the air conditioner has been running normally for a while, if the air blowing on you feels cool and quickly reaches the set temperature, and the outdoor compressor works intermittently like a refrigerator (on for a while, then off for a while), it indicates normal operation. Otherwise, refrigerant may need to be added. Method 2: Use a thermometer to measure the temperature difference between the air inlet and outlet of the indoor unit. A difference of more than 8°C is normal—the larger the difference, the better the air conditioner's performance (a good one can reach around 15°C). If the difference is below 8°C, refrigerant may need to be added. Method 3: After running for more than ten minutes, open the panel of the indoor unit. If the copper tubes of the evaporator, which are covered with aluminum fins for heat exchange, are evenly covered with condensation, it is normal. More condensation occurs when air humidity is high, and less when it is low. If not, refrigerant may need to be added. Method 4: Check the pipe joints of the indoor unit and the valves of the outdoor unit for obvious signs of oil leakage. If there is obvious oil leakage, it indicates a refrigerant leak, as oil and refrigerant are mutually soluble—oil leakage means refrigerant leakage, and vice versa.