What is the pressure of automotive air conditioning refrigerant?
2 Answers
The pressure of automotive air conditioning refrigerant varies under different conditions: 1. When the compressor is running at 1500 to 2000 rpm, the high pressure is approximately 1.5 to 2.0 MPa, and the low pressure is around 0.15 to 0.35 MPa. 2. At idle speed, if the ambient temperature is high or under direct sunlight, the high pressure may be slightly higher, reaching about 2.5 to 2.8 MPa, but it generally does not exceed 3.1 MPa. Normally, cars do not need to add refrigerant for 3 to 5 years, but sometimes if the cooling effect is poor, it may be necessary to add refrigerant. After the air conditioning has been running normally for a while, the air blowing on you should feel cool and quickly reach the set temperature. The outdoor compressor should operate like a refrigerator, sometimes working and sometimes stopping, which indicates normal operation. Otherwise, it may need refrigerant.
When I think about car air conditioning pressure, I remember what I learned from repairing cars in my younger days. The low-pressure side is generally between 25 to 35 PSI, while the high-pressure side is around 150 to 250 PSI. However, this heavily depends on the weather. During the scorching summer heat, the pressure can skyrocket to over 280 PSI, while in the freezing winter, it might drop below 150 PSI. Unreliable pressure can directly ruin the cooling effect, making the car interior feel like a steamer and also shortening the compressor's lifespan. I've also noticed that many people mess things up by casually adding refrigerant. In reality, you need to use a professional pressure gauge to measure—testing both high and low pressure will tell you if everything is normal. Never try to DIY repairs—my colleague once messed around and ended up with a gas leak that sprayed cold air right into his face, which was terrifying. Make sure to get regular checks at a maintenance shop, and don’t wait until the AC breaks down to think about it.
