What is the normal pressure for a car air conditioner?

[SanEsther]

When the compressor is running at 15002000 rpm, the high pressure (discharge pressure) should be around 1.52.0 MPa, and the low pressure (suction pressure) should be around 0.15~0.35 MPa. The exact values depend on the specific vehicle's air conditioning system configuration and ambient temperature. Here is some additional information: Air Conditioning System: The car air conditioning system is a device that cools, heats, ventilates, and purifies the air inside the vehicle cabin. Function Introduction: It provides a comfortable environment for passengers, reduces driver fatigue, and improves driving safety. The air conditioning system has become one of the indicators of whether a car is fully equipped with necessary functions.

[DeCamilla]

I usually pay attention to the air conditioning status when driving. The normal pressure for a car's air conditioning system is generally around 25 to 45 PSI on the low-pressure side and 150 to 250 PSI on the high-pressure side. These values can actually be affected by ambient temperature—for example, pressure may be higher on extremely hot days. Last time, my car's vents were blowing hot air, and it turned out to be due to refrigerant leakage causing the pressure to drop too low. So, I recommend checking the pressure gauge at least once a year, especially before summer. Measuring the pressure requires specialized equipment, and you can usually find the high and low-pressure ports by opening the hood. If the pressure is found to be out of range, it could be due to insufficient refrigerant or a compressor malfunction. Never try to tough it out—take it to a professional repair shop immediately, or you risk damaging the entire air conditioning system.

[ChristopherRose]

As someone who frequently tinkers with cars, I've done specialized research on AC pressure. The normal low pressure is 25-45 PSI, and high pressure is 150-250 PSI - these values apply to most gasoline vehicles. Measurements should be taken when the compressor is running, and note that ambient temperature affects readings; pressure at midday in summer can be about 10% higher than in the early morning. I've seen dangerous situations where people mistakenly loosened high-pressure lines - refrigerant spraying out at dozens of degrees below zero can cause frostbite. If abnormal pressure is detected, it's best to simultaneously check refrigerant levels and condenser fins, as clogged debris can cause pressure to rise. Actually, an overly dirty cabin air filter can also affect cooling performance, often being mistakenly diagnosed as a pressure issue.

[DeMadison]

Last year, my car's air conditioning suddenly stopped cooling, so I specifically studied pressure knowledge. The repair manual states that the ideal pressure should be between 30-40 PSI for the low side and 170-220 PSI for the high side. To measure the pressure, you need to use a gauge with color-coded hoses—red connects to the high-pressure line, and blue connects to the low-pressure line. A key point: if the engine RPM fluctuates too much, the pressure will vary, so I always check it while the car is idling. Previously, I encountered a situation where the low-pressure gauge consistently read below 25, indicating a refrigerant leak. The mechanic had to use fluorescent dye to locate the leak. I recommend checking the pressure during every maintenance service to catch issues early and save a lot of money.

[DiLilah]

Years of driving experience have taught me that the normal pressure for air conditioning is 25-45 PSI for low pressure and 150-250 PSI for high pressure. Remember, the unit is PSI, not bar. It's best to measure under temperatures of 25-35°C, as readings are inaccurate when it's too cold or too hot. I always keep a mini pressure gauge in my car and check it when the cooling slows down. A common issue is high pressure exceeding 250 PSI, usually due to poor condenser cooling or fan failure—check if the radiator fins are clogged with catkins. Low pressure below 25 PSI might indicate a faulty expansion valve needing replacement. Also, ensure the refrigerant type matches; R134a should never be mixed with R12, as it causes abnormal pressure.