What is the general pressure for car air conditioning pressure testing?
2 Answers
Car air conditioning pressure testing generally requires a pressure of 20-30 bar. Below are the functions and precautions for car air conditioning pressure testing: Functions of car air conditioning pressure testing: The purpose of car air conditioning pressure testing is to check whether the air conditioning leakage issue has been resolved and to verify the sealing performance of the car air conditioning system. The air conditioning pressure must stabilize at 20-30 Bar before proceeding with vacuuming and refrigerant charging. Precautions for car air conditioning pressure testing: The pressure for car air conditioning testing should be higher than the working pressure of the air conditioning system. During testing, the low-pressure side should be vacuumed while the high-pressure side is pressurized. The low-pressure gauge must be disconnected during pressure testing to avoid damage.
For a standard automotive AC pressure test, the procedure calls for pressurizing up to around 250 psi as the upper limit. However, with twenty years of repair experience, I've always stopped at 200 psi. In aging systems, higher pressures risk hose bursts—especially in vehicles over a decade old. This test primarily detects leaks, but remember: rigorous vacuuming for at least 30 minutes is mandatory beforehand. Always use nitrogen cylinders to maintain pressure; standard air tanks introduce moisture that can damage compressors. If pressure drops exceed 10% post-test, recheck for leaks before even considering refrigerant recharge—rushing this step invites serious consequences.
