Air conditioning system has gradually become the standard equipment of cars. There are many kinds of air conditioners used in automobiles, and their structures are similar. The maintenance interval shall be generally once a year or as required. If it is found that the refrigeration effect is not good in use, it should be checked. The fault is usually caused by refrigerant leakage. Inspection and repair can be carried out through the following steps.

1.查找泄漏部位

1. Find the leakage part

目前車輛上使用的空調系統一般為單冷開啟式，制冷劑多采用氟里昂（R12或氟里昂的替代產品134a）。在使用中，制冷劑易從各連接接頭、油封處泄漏，制冷劑泄漏將會導致制冷效果差或不制冷等現象。

At present, the air conditioning system used in vehicles is generally single cold open type, and the refrigerant is mostly Freon (R12 or alternative product 134a of Freon). In use, the refrigerant is easy to leak from the connection joints and oil seals, which will lead to poor refrigeration effect or no refrigeration.

（1）檢查漏油痕跡。在空調制冷循環系統中，冷卻油是用來潤滑密封軸承以及壓縮機內其他運動部件的，少量的潤滑油將會與制冷劑一起進入制冷循環系統中。如果制冷循環系統發生泄漏，泄漏處就會出現油漬，所以在檢查中，發現管路及接頭處有油漬，就可以確定該處有泄漏故障，應進行修理。

(1) Check for traces of oil leakage. In the air conditioning refrigeration cycle system, the cooling oil is used to lubricate the sealed bearing and other moving parts in the compressor. A small amount of lubricating oil will enter the refrigeration cycle system together with the refrigerant. If the refrigeration cycle system leaks, there will be oil stains at the leakage. Therefore, if there are oil stains on the pipelines and joints during the inspection, it can be determined that there is a leakage fault at this place, which should be repaired.

（2）觀察檢視窗，判定制冷劑泄漏情況。起動發動機（約1000r/min），打開制冷控制開關（A/C），將溫度開關控制桿置于COLD（冷）位置，風扇開關開到的位置，可以從檢查窗處觀察到制冷劑的流動狀態，來判斷制冷循環系統中有無泄漏。

(2) Observe the inspection window to determine the leakage of refrigerant. Start the engine (about 1000r / min), turn on the refrigeration control switch (A / C), set the temperature switch control lever to the cold position, and turn on the fan switch to the maximum position. The flow state of refrigerant can be observed from the inspection window to judge whether there is leakage in the refrigeration cycle system.

制冷劑流動正常：制冷劑大體上透明，此時出風口的風是冷的。制冷系統的狀態正常。

The refrigerant flow is normal: the refrigerant is generally transparent, and the air at the air outlet is cold. The state of the refrigeration system is normal.

制冷劑不足：制冷劑不足時，就會經常看到氣泡流動，制冷劑呈乳白色，這時制冷效果不佳。

Insufficient refrigerant: when the refrigerant is insufficient, bubbles will often be seen flowing, and the refrigerant is milky white, and the refrigeration effect is poor.

沒有制冷劑：如果制冷系統嚴重泄漏，觀察玻璃窗內就什么也看不到，此時空調系統不會制冷。富康轎車的儲液罐上有A、B兩個檢視窗。檢視窗A可以判斷儲液罐中干燥劑的水分含量是否飽和。若呈藍色，表示正常；若呈紅色，表示水分已呈飽和狀態。應緩慢的排盡空調系統中的制冷劑，更換儲液罐中的干燥劑，然后重新加注制冷劑。B檢視窗的作用和前面介紹的內容相同，主要用于觀察制冷劑的情況。

No refrigerant: if the refrigeration system leaks seriously, nothing can be seen in the observation glass window. At this time, the air conditioning system will not cool. There are two inspection windows a and B on the tank of Fukang car. Inspection window a can judge whether the moisture content of the desiccant in the reservoir is saturated. If it is blue, it means normal; if it is red, it means that the water is saturated. The refrigerant in the air conditioning system should be drained slowly, the desiccant in the reservoir should be replaced, and then the refrigerant should be refilled. The function of the B inspection window is the same as that described above. It is mainly used to observe the condition of refrigerant.

在檢查時，所有連接部位或冷凝器表面一旦發現油漬，一般都說明此處有制冷劑泄漏。發現有泄漏現象時，應及時進行排除泄漏故障，補充制冷劑和潤滑油，以防泄漏潤滑油，損壞空調系統。

In the inspection, once oil stains are found on all connection parts or condenser surface, it generally indicates that there is refrigerant leakage here. In case of leakage, the leakage fault shall be eliminated in time, and the refrigerant and lubricating oil shall be supplemented to prevent the leakage of lubricating oil and damage to the air conditioning system.

2.檢查空調系統的工作情況

2. Check the working condition of air conditioning system

檢查時將汽車停放在通風良好的場地上，保持發動機中等轉速，將空調機風速開到擋，使車內空氣內循環。

During the inspection, park the car in a well ventilated place, keep the engine at medium speed, turn the air conditioner to the maximum speed, and circulate the air inside the car.

（1）從各部的溫度判斷空調狀態。用手觸摸空調系統及各部件，檢查表面溫度。正常情況下，低壓管路呈低溫狀態，高壓管路呈高溫狀態。

(1) Judge the air conditioning state from the temperature of each part. Touch the air conditioning system and its components by hand to check the surface temperature. Under normal conditions, the low-pressure pipeline is in a low-temperature state, and the high-pressure pipeline is in a high-temperature state.

高壓管路：壓縮機出口→冷凝器→儲液罐→膨脹閥進口處。這些部件應該先暖后熱，手摸時應特別小心，避免被燙傷。如果在其中某一點發現有特別熱的部位，則說明此處有問題，散熱不好。如果某一點特別涼或結霜，也說明此處有問題，可能有堵塞。干燥儲液器進出口之間若有明顯溫差，說明此處有堵塞。

High pressure pipeline: compressor outlet → condenser → liquid storage tank → inlet of expansion valve. These parts should be warmed first and then heated. Special care should be taken when touching them to avoid scalding. If a particularly hot part is found at one point, there is a problem here and the heat dissipation is not good. If a certain point is particularly cold or frosty, it also indicates that there is a problem here and there may be blockage. If there is obvious temperature difference between the inlet and outlet of the drying reservoir, it indicates that there is blockage here.

低壓管路：膨脹閥出口→蒸發器→壓縮機進口，這些表面應該由涼到冷，但膨脹閥處不應發生霜凍現象。

Low pressure pipeline: expansion valve outlet → evaporator → compressor inlet, these surfaces should be from cold to cold, but frost should not occur at the expansion valve.

壓縮機高低側之間應該有明顯的溫差，若沒有明顯溫差，則說明空調系統內沒有制冷劑，系統有明顯的泄漏。

There should be obvious temperature difference between the high and low sides of the compressor. If there is no obvious temperature difference, it means that there is no refrigerant in the air conditioning system and there is obvious leakage in the system.

（2）清理空調裝置上的雜物。檢查蒸發器通道及冷凝器表面，以及冷凝器與發動機水箱之間（停機檢查）是否有雜物、污泥，要注意清理，仔細清洗。冷凝器可用毛刷輕輕刷洗，注意不能用蒸氣沖洗。

(2) Clean the sundries on the air conditioner. Check the evaporator channel and condenser surface, as well as between the condenser and the engine water tank (shutdown inspection) for debris and sludge. Pay attention to cleaning and cleaning carefully. The condenser can be gently brushed with a brush, and it should not be washed with steam.

（3）檢查調整空調皮帶。檢查皮帶松緊度是否適宜、表面是否完好（與發動機皮帶檢查調整相同）。以上檢查如果發現異常時，應進行修理。

(3) Check and adjust the air conditioning belt. Check whether the belt tightness is appropriate and whether the surface is intact (the same as the engine belt inspection and adjustment). If any abnormality is found in the above inspection, it shall be repaired.