What is the normal pressure for a car's air conditioning system?
4 Answers
Under normal operating conditions of a general car's air conditioning system, the low pressure should be between 1.0-2.5 bar, and the high pressure should be between 15-18 bar. Here is some extended information on how to maintain a car's air conditioning system: 1. Comprehensive inspection of the air conditioning system: When using the air conditioning for the first time in summer, it is advisable to inspect the system first, such as checking the refrigerant and whether the air filter is too dirty through the reservoir, and whether there are any foreign objects in the radiator. 2. Pay attention to cleaning the air conditioning: Waiting until the air conditioning performance deteriorates before cleaning is not the right approach. The air filter should be replaced regularly. For example, in spring when there is more sand and dust, and willow catkins are flying around, these can stick to the filter, promoting bacterial growth and causing a musty smell in the air conditioning. Additionally, the condenser should be cleaned periodically, and the radiator should be removed for thorough cleaning.
In my over ten years of experience repairing cars, the normal pressure of car air conditioning varies depending on the type of refrigerant. For example, the mainstream R-134a refrigerant typically has a low-pressure side between 25 to 45 psi and a high-pressure side around 150 to 200 psi. These values are greatly affected by ambient temperature. Higher pressure on hot days is normal, but if the low pressure is below 25 psi or the high pressure exceeds 250 psi, it may indicate refrigerant leakage or system blockage causing the air conditioning to not cool. Car owners can buy a dedicated pressure gauge to simply measure it, but if inexperienced, never touch the refrigerant as it is toxic. It is recommended to go directly to a professional repair shop where they can diagnose and repair it for you to avoid accidents.
As an average car owner, I've experienced air conditioning failure before. It wasn't until I went to the 4S shop that I learned about pressure issues - normal low pressure should be between 25 to 45 psi, while high pressure ranges from 150 to 200 psi. During summer road trips, it's common for high pressure to spike up to 220 psi. However, if the pressure remains consistently too low, it might indicate insufficient refrigerant needing replenishment. That time, I solved the problem by spending 200 yuan to recharge the refrigerant. I recommend checking the AC system annually before problems become serious, ensuring cool air inside for safe driving. Choosing a trusted repair shop for inspection gives peace of mind.
When I first started driving, I was completely confused about the AC pressure. Later, I learned that the standard is 25-45 psi for low pressure and 150-200 psi for high pressure. In hot weather, the pressure naturally tends to be higher. If the AC blows warm air, it might be due to low pressure or a refrigerant leak. Beginners should avoid DIY attempts as they are risky—it's best to go directly to a professional auto service center. Now I feel much more at ease while driving.
