How much the pressure of the car air conditioner is normal, how to read the reading of the pressure gauge of the car air conditioner

When the automobile air conditioning refrigeration system is working, the high and low pressure side pressures in the system have a normal working range, but what is the normal pressure of the automobile air conditioning? There must be a lot of friends who don’t know, so let’s get to know it together.

How to read the readings of the car air conditioner pressure gauge

Automobile air-conditioning pressure gauges are generally not high-pressure gauges and low-pressure gauges, the red one is the high-pressure gauge, and the blue one is the low-pressure gauge. Generally, the reading units on the table are megapascals (mpa), some bar (bar), some kilopascals (kpa), and some pounds per square inch (psi). The conversion between the units is 1mpa=10bar=1000kpa=145psi.

The low pressure side pressure gauge is used to display pressure and vacuum degree. Generally, the absolute pressure range of vacuum reading is 0-101.3kPa, and the pressure scale starts from the gauge pressure of 0MPa, and the range should be 1.5MPa. The pressure range measured by the pressure gauge on the high pressure side starts from the gauge pressure of 0 MPa, and the range should be 3 MPa.

Normal pressure of car air conditioner

When the car air conditioner is running, the normal high pressure is 1.3-1.7mpa (13-17bar) and the low pressure is 0.1-0.25mpa (1-2.5bar), but the normal pressure of the air conditioner will also change due to changes in the external environment.

The automobile air-conditioning pressure gauge is used to detect the refrigeration system. If the degree of the pressure gauge does not match the normal value, it indicates that the refrigeration system may be faulty:

① When the car air conditioner pressure gauge shows low pressure and high pressure, it may be a lack of refrigerant, which is a common phenomenon. Some cars have been used for a long time, and there will be refrigerant leakage failures. After maintenance, you can directly add refrigerant to solve the problem.

②When the car air conditioner pressure gauge shows high pressure and high pressure, it may be a failure of the expansion valve normally open.Car cooling is not good, connect the pressure gaugediscoverThe low pressure and high pressure are both high. It may be that the expansion valve is in a normally open state, causing air to appear in the refrigeration system. The high and low pressures are mixed, which makes the cooling effect of the air conditioner worse. Replace the expansion valve to solve the problem.

③When the automobile air-conditioning pressure gauge shows low-pressure vacuum (the pointer is below 0 scale), and the high-pressure is low, it may be a failure of the expansion valve to close. The car is not cooling, this kind of failure is usually the evaporator expansion valve is closed, but also to replace the expansion valve.

④ When the car air conditioning pressure gauge shows that the low pressure gauge is sometimes normal, sometimes vacuum, and the high pressure is sometimes normal, sometimes low, it may be that there is moisture in the refrigeration system. When the water freezes in the pipeline, it will cause a vacuum phenomenon in the low-pressure pipeline. After the ice freezes, the system is normal again. At this time, the only way to release the refrigerant in the system, re-vacuum, and refill the refrigerant.

⑤ When the car air-conditioning pressure gauge shows high low pressure and low high pressure, it may be a compressor failure. If this phenomenon occurs in the pressure gauge, there is a lot of refrigerant in the pipeline, and the air conditioning effect is not good. At this time, it is necessary to consider the failure of the air conditioning compressor. There may be leakage inside the compressor. Generally, replacing the compressor can solve the problem.