What is the correct method for adding refrigerant to a car?
2 Answers
There are two methods for adding refrigerant: 1. High-pressure side charging: Refrigerant is added through the bypass port (multi-purpose channel) of the compressor discharge valve (high-pressure valve), known as high-pressure side charging, which involves adding liquid refrigerant. This method is characterized by safety and speed, making it suitable for the initial charging of the refrigeration system, i.e., after leak detection and vacuuming. However, it is important to note that the compressor must not be turned on during this process (the engine must be off), and the refrigerant can must be inverted. 2. Low-pressure side charging: Refrigerant is added through the bypass port (multi-purpose channel) of the compressor suction valve (low-pressure valve), known as low-pressure side charging, which involves adding gaseous refrigerant. This method is characterized by slower charging speed and is suitable for replenishing refrigerant in the system.
As someone who has worked in auto repair shops for years, I believe the correct method of adding refrigerant requires careful step-by-step procedures. Wearing goggles and gloves is mandatory, as refrigerant can cause frostbite upon skin contact. First, check the AC system for leaks by spraying soapy water on pipe connections to observe bubble formation. Connect the charging kit to the low-pressure port labeled L, then start the engine with AC set to maximum cooling and fans at highest speed to facilitate circulation. Slowly inject refrigerant while monitoring the pressure gauge to ensure it doesn't exceed the vehicle manual's specified range, which could damage the system. After charging, run the system for a few minutes to verify proper cooling performance before shutting it off. Always perform the procedure in well-ventilated areas to minimize inhalation risks. I recommend beginners go directly to professional shops for proper handling to avoid costly mistakes.
