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Car Air Conditioning Maintenance Tips

When summer arrives, car air conditioners will begin their hard work for a year. When the owner sweated eagerly to open the car air conditioner and was ready to enjoy the coolness brought by the air conditioner, unfortunately, it was found that the car air conditioner did not work. In summer, without the air-conditioned cool air, we can only steam in the cabin. In order not to be a victim of the summer, so we have to check the air conditioning of vehicles before summer.

How to maintain automotive air conditioners:

We will meet with the question 1 – air conditioning refrigeration is not to force:

For automotive air conditioners, the most common problem we face is that – after a winter, the cooling capacity of air conditioners is reduced when the air conditioner is turned on; even the air outlets of some vehicles will blow hot air.

The air conditioning system of the vehicle is composed of many metal pipelines. There is a small gap between the pipelines. Therefore, the refrigerant in the air-conditioning system (“snow species”) is strictly a leak but in general, less leakage is also extremely serious. At the same time, the dry bottle in the air conditioning system (“to absorb the water present in the refrigerant”) also stores a part of the refrigerant due to the adsorption of moisture, resulting in the reduction of the refrigerant in the air conditioning system. When the amount of refrigerant in the air-conditioning system is reduced to a certain level, it will lead to insufficient cooling of the air-conditioner, and some models with air-conditioning and air-conditioning also blow hot air out of the outlet due to insufficient cooling (Air conditioning heating air principle: the coolant passes through the hot water evaporator and the air is warmed from the grille on the evaporator)

In this case, we can judge the inventory of air-conditioning system snow through the high and low pressure pipeline pressure of the air-conditioning system when cooling the air-conditioning system. The air-conditioning high-low pressure inspection pipeline is located in the engine compartment and can be inspected using a dedicated pressure gauge. When the air conditioning system is in operation, the pressure in the high pressure line should be about 13.7 bar and the pressure in the low pressure line should not be lower than 2.5 bar.

Noted: (1 MPa = 10.19718 kgf/cm2= 145.03725 psi = 10bar )

If the pressure in the air-conditioning high- and low-pressure pipes is found to be much lower than the standard pressure, the refrigerant in the air-conditioning system is insufficient. In this case, we need to add refrigerant and test the air-tightness of the air conditioning system. The practice is to pump out the refrigerant from the air-conditioning system and maintain a negative pressure of 1 bar. Wait 24 hours to see if the air pressure in the system is maintained at about -1 bar. And if the air pressure rises significantly, there is a leak in the air conditioning system and further disassembly inspections are required. If the air-conditioning system does not leak, then we can add the appropriate amount of refrigerant according to the vehicle model.

Assuming that the air-conditioning system does not leak, pumping refrigerant can solve most of the air-conditioning problems without cooling. It takes only few $ to add refrigerant and test the air-conditioning system’s tightness.

We will encounter problem 2 – air conditioning is not cooling:

The air-conditioner is not cooled at all. In addition to the lack of refrigerant, the compressor does not work is also a reason. The compressor of the air conditioning system is now equipped with a clutch. The compressor works only when the clutch is closed. If the compressor fails to switch to the pull-in state, then the air-conditioner will not be cooled.

After the refrigerant is pumped and the air-conditioning system is tested for tightness, the problem that the air-conditioner is not cooled at all is still not solved. Then the replacement of the compressor is the main work to be done next. Replacing the compressor requires first evacuating the air conditioning system refrigerant and then replacing the compressor. After replacing the compressor, it is also necessary to check the air-conditioning system tightness and fill the refrigerant.

The problem 3 that we will meet – the unknown air from the air outlet:

In some cases, when we turn on the air conditioner, we will find that there is a lot of white gas blowing from the air outlet. These gases are actually vaporized refrigerants. This happens because the evaporator inside the center console has leaked. We can only replace the air conditioner evaporator inside the center console. We are skeptical of those trapping products on the market and we recommend that car owners not use related products.

Replacing the evaporator is a relatively large project that requires evacuating the refrigerant and dismantling the center console.

Problems we will meet 4 – Air conditioning abnormal sound

Air conditioning abnormal sounds may feel due to abnormal sounds in the air conditioning system or abnormal noises which comes from outer side of air conditioning system. The internal abnormal sound is usually the air or moisture in the refrigerant in the system. When the refrigerant evaporates and expands, abnormal sound occurs. The user feels that there is a noise inside the center console; the external noise is generally the abnormal sound of the air conditioner compressor, near the air conditioner compressor we can feel the sound.

Such abnormal sound is generally caused by the air and moisture doped in the refrigerant composition. If the condition is still after the refrigerant is pumped, then the abnormal sound is located near the compressor and the internal mechanical structure of the compressor is more likely to be damaged; if the abnormal sound recurs after a period of time, and a position is located inside the center console, the drying bottle has a higher probability of reducing the efficiency.

This article analyzes all common vehicle air conditioning system failures and hopes to help everyone with their cars. When the summer is approaching, the owners of the vehicle should check whether the air-conditioning system of the vehicle is working well and prepare for it as soon as possible.