What Causes an Air Conditioning System to Hold Pressure but Leak Refrigerant?

[DeOwen]

Most likely, it is due to damage at the refrigerant charging port. 1. Detection Method: After charging the AC system with refrigerant, remove the charging hose and spray soapy water onto the refrigerant port of the AC lines to check for bubbles. 2. Solution: Replace the valve core of the AC charging port (specific structure can be referenced to a standard bicycle Schrader valve). Additional relevant information is as follows: Notes: Based on the owner's description of the refrigerant leaking out within a month, it can be inferred that the leak point is likely very small. Due to the complexity of the AC line locations in vehicles, disassembly for inspection can be challenging. It is recommended to use "fluorescent leak stop and detection agents." This substance can be added to the refrigerant line; if the leak is small, it may temporarily seal the leak. If the leak persists, the fluorescent dye contained in the agent will clearly indicate the leak point under UV light, facilitating subsequent repair work.